arewell rookie: a comprehensive understanding of memory technology parameters

Sep.02, 2011 inUncategorizedComments Off

Such a small memory hardware, PC system is the most important and indispensable part of. For entry-users, may be from memory type, frequency, interface type impression of these simple parameters may be very vague, but for more in-depth small parameter of the memory timing is even more puzzled. For advanced players, the memory of some specific parameters is small enough to affect the entire system overclocking results and the final performance. If you do not want to rookie then, though not necessarily take a variety of parameter specifications eleven memorize, but at least have a basic understanding of other really need to use the time to check up and will not have no idea.
At present, the memory used in desktop platform mainly DDR1, DDR2 and DDR3 three, which has largely been eliminated DDR1 memory, and DDR2 and DDR3 is mainstream.
DDR1 memory

DDRSDRAM is DoubleDataRateSDRAM abbreviation is double data rate synchronous dynamic random access memory means. SDRAM memory DDR memory is developed on the basis of, the continued use of SDRAM production system, so for the memory manufacturers, only production of common SDRAM devices for a little improvement, you can achieve the production of DDR memory, which can effectively reduce the costs.
DDR2 Memory
DDR2 memory is DDRSDRAM the second generation of products. It is based on DDR memory technology to be improved, thus the transmission faster (up to 800MHZ), lower power consumption, better thermal performance.
DDR3 memory

DDR3 DDR2 compared to a lower operating voltage, from 1.8V of DDR2 landing to 1.5V, even better performance of power; DDR2 upgrade of 4bit 8bit pre-reading pre-reading. To 1600Mhz DDR3 highest speed, the current speed of the fastest DDR2 memory speed has been upgraded to 800Mhz/1066Mhz, which first DDR3 memory modules will take-off from the 1333Mhz.
between three types of DDR memory, from memory controller to the memory slots are not compatible. Even some support both types of memory, Combo motherboard, two sizes of memory can not work simultaneously, only one memory.

SPD (SerialPresenceDetect): SPD is an 8-pin EEPROM (ElectricallyErasableProgrammableROM electrical erasable programmable read-only memory), a capacity of 256 bytes, which preserved the memory of the main relevant information, such as capacity , chip manufacturers, memory module manufacturers, working speed. The contents of the SPD is generally written by the memory module manufacturers. The motherboard supports the SPD automatically when you start testing the SPD data and operating parameters in order to set the memory.
start the computer, the motherboard BIOS will read the SPD information, motherboard Northbridge chipset information will be based on these parameters to automatically configure the appropriate timing and working memory control register, which can give full play to the memory of performance. Prerequisite for achieving the above is in BIOS setup, set the memory option to “BySPD”. When the board can not be detected from the memory to the SPD information, it can only provide a more conservative configuration.
sense, SPD memory chip is to identify an important symbol of the brand. If the SPD within the parameters set unreasonable, not only can not play a role in memory optimization, but also cause system instability or even crash. Therefore, many common memory or compatible memory manufacturers in order to avoid compatibility problems, generally the work of the SPD in the memory parameter in a more conservative, thus limiting the memory performance of the full play. Worse, some unscrupulous manufacturers through a special reader device to change the SPD information to fool the computer test, is inconsistent with the actual data obtained .
IntelExtremeMemoryProfiles called XMP, which is a technique to improve memory performance, technology and NVIDIA SLIMemory similar. Intel developed a IntelExtremeMemoryProfiles (IntelXMPSpecification), DDR3 memory will make certification chipset will automatically recognize the specified brand and certified memory modules specified model by increasing data throughput, increased bandwidth and other means to increase its performance.
Intel said that as the major future-oriented high-end platform, the technology does not appear in the DDR2 memory module, in order to use the “ExtremeMemory” technology, the first condition is to use DDR3 memory.
memory controller (MemoryController)
memory controller is a computer system memory and internal control by the memory controller to switch between memory and CPU an important part of the data. Memory controller can be used by the computer system determines the maximum amount of memory, memory BANK number, memory type and speed, memory depth and data width of the particle data so important parameter that determines the computer system memory performance, which also the overall performance of computer systems have a greater impact.
early memory controller integrated on the motherboard Northbridge
traditional computer system memory controller on the motherboard chipset North Bridge chip, CPU and memory to exchange data, need to go through “CPU – Northbridge – Memory – Northbridge – CPU” five steps, in this mode of data transmission through the multi-level, data delay is clearly larger computer system which affects the overall performance; and AMD K8 series CPU (including Socket754/939/940 various other interface processors) within the integrated memory controller, CPU and memory on the data exchange process between the simplified “CPU – Memory – CPU” three steps, omitted two steps, and compared to a traditional memory controller program clearly has a lower data latency, which helps improve the overall performance of computer systems.
AMD took the lead in the desktop platform, the memory controller integrated in CPU
Intel new Core Duo processor family also integrate the memory controller
CPU internal advantage of the integrated memory controller, memory controller that can effectively control the work of the same with the CPU core frequency, and because memory and CPU without going through the data exchange between the North Bridge, can effectively reduce the transmission delay. Analogy, it is like to move the goods directly to the warehouse next to the processing plant, greatly reducing the raw materials and finished goods warehouse and processing plant in the round-trip transportation between the time required, greatly improved production efficiency. As a system overall performance has improved.

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Glossary An roid system summary

Sep.02, 2011 inUncategorizedComments Off

1, firmware, firmware brush
Firmware is the software solidified, English for the firmware, it is to write a system program to a specific hardware system flashROM.
mobile phone firmware is equivalent to the system, flush the firmware is equivalent to the brush system. Different mobile phone corresponding to different firmware, the brush should fully understand the current firmware before the firmware and the firmware of the merits of the brush and compatibility, and fully prepared.
2, ROM (package)
smartphone configuration ROM refers EEProm (electrically erasable read-only memory can be written) similar in the computer hard disk, mobile phones can store many things to see if he capacity. End of package update package referred to as a ROM package.
3, firmware version
firmware version is the official release of firmware version number! Which contains the application and baseband part of the update part of the update, the official launch of the new firmware, the main purpose is to repair the previous years, there is a BUG and firmware to optimize performance related.
4, CID, SUPERCID
CID is CustomerIDentity short, is simply a platform for mobile phone version, known as the CID after the break limit SUPERCID.
Brush the process need to CID-tested SPL ROM is available, and decide whether to brush into, under normal circumstances required by law to correspond with the CID ROM can, cid different rom is the brush can not get . For ordinary CID, the general has two limitations: 1) can not brush into the low version of the ROM, 2) can not brush into the different platforms of the ROM, for example: in Taiwan version of the machine brushes the European version of ROM, ROM, etc. across the brush model . SUPERCID some phone models to crack software, known there are 577W, 586W and so on, but there are also some models there is no effective way to break the CID, such as 838G4.
after cid limit break is called SUPERCID, the machine can brush with SUPERCID any version and platform of the ROM. Specifically, a mobile phone with both brush Taiwan ROM, you can brush the Japanese rom, rom Hong Kong can also brush and so on. You can even brush into one of the other model phones ROM (such as the 586W brush 577W). But it also brings great danger, because there is no limit, no parity, an error brush into the ROM is very easy. We generally need to break the Brush SUPERCID, because in most cases now the one hand, brush machine is used to pass the CID ROM checksum; the other hand, in case of brush failure, the mobile phone is easier for SuperCID repair.
5, HTCSense, Motorola Blur, Samsung TouchWiz , etc.
HTCSense for the Android system design, user interface. Starting from HTCHero, HTC launched the all products will integrate HTCSense. And meet the three design concepts, including MakeItMine, StayClose, and DiscovertheUnexpected.
Motorola Blur is based on the Google Android platform application interface, in addition to the basic features of the Android addition, Blur most prominent feature is the emphasis on social networking features. Blur has now integrated a lot of well-known social networking components, including Facebook, Twitter, Gmail, MySpace, Yahoo, Picasa, etc., as long as the user Email account bound with social networking, from the information on these social networks automatically pushed to mobile phones.
Samsung TouchWiz This technology allows the dynamic drag and drop icons and interface smooth handoff. In all fairness, all of Samsung previous “command and control system” can only be regarded as semi-finished products! Only in the non-touch system touch system is modified it. The TouchWiz mode of operation is completely different, and several mobile phones before, and whether it is operating or input method menu interface is very suitable for finger control. Apple multi-point technology and the technology is almost, is not the same as it is called!
6, Recovery
general, said the project is a brush machine interface. If you had installed the system, you probably know dos interface or winPE, install the Recovery equivalent to the system security of a dos interface. You can choose to install the system recovery screen, clear data, ghost backup system, restore the system and so on. Brush and brush rom do not conflict recovery.
7, APPTOSD, APP2SD
some Android machine when the installation program is installed by default on the machine memory, which will lead to the original much memory is occupied, the speed reduced, but utilization is very low memory card case. APPTOSD is to install to the SD card to free up phone memory to improve the speed of the mean. APP2SD no exception, but harmonics only.
8, Root
Root privileges with our Administrator rights under Windows system can be understood as a concept Root is the super Android system administrator user account, which has a paramount right to the whole system, all the objects that he can operate. We only have this permission can be refreshed for the revision of the original system of systems, such as simplified Chinese system.
9, RADIO
Radio is a simple wireless communications module of the driver. ROM is a system program, Radio is responsible for network communications, ROM and Radio can be separated from brush, independently of each other. If your cell phone to refresh the ROM after communication problems can try to refresh RADIO.
10, ROM category
generally divided into two categories, one is from the official mobile phone manufacturers original ROM, is characterized by stability, function with the vendor-specific and are different; the other is the development of enthusiasts to the official release of source code self-compiled native ROM, is characterized by the specific needs of the user to adjust, to make ROM more in line with consumer behavior in different regions.
11, IPL, SPL
IPL English name is InitialProgramLoader, responsible for the motherboard, power supply, hardware initialization process, and into the SPL RAM. IPL damage that can be thrown into the river a mobile phone, or by changing font to resolve.
SPL English name is SecondProgramLoader, “the second loading system” is responsible for loading the OS operating system into RAM. SPL also includes many other system commands, such as mtty used in orders. SPL damaged burner can also rewrite.
SPL generally provide some of these functions: Detection of mobile phone hardware, find system boot partition, boot the operating system to provide basic maintenance for the system user interface, through the data line and the terminal (eg PC) to establish a connection and to receive and execute the corresponding command. It contains many commands, like r2sd, l, doctest (dangerous command, he would erase gsmdata) and so on. We often say that the three-color screen is driven by the SPL. Detect the SD card when you make some special SD card inserted, SPL can check at startup according to brush machine or the SD card content to execute commands. This is somewhat similar to the PC from the floppy drive.
IPL and SPL version can be viewed in the tri-color screen. Hold down the camera key, then press the power button to boot into the tri-color screen to view information.
12, Sign
Sign Rom is to sign the application package or Apk, only signed off Apk Rom or brush into the can or installed to the phone.
13, Cyanogen, CM
Cyanogen is a foreign cattle, their production CyanogenMod Rom popular series, is the main pursuit of speed , CyanogenMod abbreviation is the CM, which we have common CMROM.
14, adb
adb is AndroidDebugBridge acronym, meaning the system for the Android Debug Bridge. By adb we can respect in Eclipse to debug Android applications by DDMS, in fact, this is for Google Android system debug debugging tools.
adb work is rather special, such as the use of listening SocketTCP5554 way to let the IDE port and Qemu communications, will default associated network ports, so when we run the installer when the adb APK on the process will run automatically.
In addition to the operating functions, we can also manage the device or mobile phone emulator adb state. Can also be a lot of phone operations, such as brush ROM upgrade, run shell commands, and so on.

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Throw away the rookie tag! Comprehensive u derstanding of memory technology parameters

Sep.02, 2011 inUncategorizedComments Off

Such a small memory hardware, PC system is the most important and indispensable part of. For entry-users, may be from memory type, frequency, interface type impression of these simple parameters may be very vague, but for more in-depth small parameter of the memory timing is even more puzzled. For advanced players, the memory of some specific parameters is small enough to affect the entire system overclocking results and the final performance. If you do not want to rookie then, though not necessarily take a variety of parameter specifications eleven memorize, but at least have a basic understanding of other really need to use the time to check up and will not have no idea.
memory type
At present, the memory used in desktop platform mainly DDR1, DDR2 and DDR3 three, which has largely been DDR1 memory eliminated, while the DDR2 and DDR3 is mainstream.
DDR1 memory first generation DDR Memory
DDRSDRAM is DoubleDataRateSDRAM abbreviation is double data rate synchronous dynamic random access memory means. SDRAM memory DDR memory is developed on the basis of, the continued use of SDRAM production system, so for the memory manufacturers, only production of common SDRAM devices for a little improvement, you can achieve the production of DDR memory, which can effectively reduce the costs.
DDR2 Memory The second generation of DDR memory
DDR2 memory is DDRSDRAM the second generation of products. It is based on DDR memory technology to be improved, thus the transmission faster (up to 800MHZ), lower power consumption, better thermal performance.
DDR3 memory third generation DDR
DDR3 memory compared to DDR2 has a lower operating voltage, from 1.8V of DDR2 landing to 1.5V, more power and better performance; DDR2 upgrade of 4bit 8bit pre-reading pre-reading. To 1600Mhz DDR3 highest speed, the current speed of the fastest DDR2 memory speed has been upgraded to 800Mhz/1066Mhz, which first DDR3 memory modules will take-off from the 1333Mhz.
between three types of DDR memory, from memory controller to the memory slots are not compatible. Even some support both types of memory, Combo motherboard, two sizes of memory can not work simultaneously, only one memory.
memory SPD chip memory SPD chip
SPD (SerialPresenceDetect): SPD is an 8-pin EEPROM (ElectricallyErasableProgrammableROM electric erasable programmable read-only memory), a capacity of 256 bytes, which preserved the memory of the main information such as capacity, chip manufacturers, memory module manufacturers, working speed. The contents of the SPD is generally written by the memory module manufacturers. The motherboard supports the SPD automatically when you start testing the SPD data and operating parameters in order to set the memory.
start the computer, the motherboard BIOS will read the SPD information, motherboard Northbridge chipset information will be based on these parameters to automatically configure the appropriate timing and working memory control register, which can give full play to the memory of performance. Prerequisite for achieving the above is in BIOS setup, set the memory option to “BySPD”. When the board can not be detected from the memory to the SPD information, it can only provide a more conservative configuration.
sense, SPD memory chip is to identify an important symbol of the brand. If the SPD within the parameters set unreasonable, not only can not play a role in memory optimization, but also cause system instability or even crash. Therefore, many common memory or compatible memory manufacturers in order to avoid compatibility problems, generally the work of the SPD in the memory parameter in a more conservative, thus limiting the memory performance of the full play. Worse, some unscrupulous manufacturers through a special reader device to change the SPD information to fool the computer test, is inconsistent with the actual data obtained to deceive consumers.
XMP technology support XMP technology XMP memory products in the BIOS settings
IntelExtremeMemoryProfiles called XMP, which is a technique to improve memory performance, technology and NVIDIA SLIMemory similar. Intel developed a IntelExtremeMemoryProfiles (IntelXMPSpecification), DDR3 memory will make certification chipset will automatically recognize the specified brand and certified memory modules specified model by increasing data throughput, increased bandwidth and other means to increase its performance.
Intel said that as the major future-oriented high-end platform, the technology does not appear in the DDR2 memory module, in order to use the “ExtremeMemory” technology, the first condition is to use DDR3 memory.
memory controller (MemoryController)
memory controller is a computer system memory and internal control by the memory controller to switch between memory and CPU an important part of the data. Memory controller can be used by the computer system determines the maximum amount of memory, memory BANK number, memory type and speed, memory depth and data width of the particle data so important parameter that determines the computer system memory performance, which also the overall performance of computer systems have a greater impact. Early memory controller integrated on the motherboard Northbridge
traditional computer system memory controller on the motherboard chipset North Bridge chip, CPU and memory to exchange data, need to go through “CPU – Northbridge – - Memory – Northbridge – CPU “five steps, in this mode of data transmission through the multi-level, data delay is clearly larger computer system which affects the overall performance; and AMD K8 series CPU (including Socket754/939/940 etc. interface to a variety of processors) within the integrated memory controller, CPU and memory on the data exchange process between the simplified “CPU – Memory – CPU” three steps, two steps omitted, and the traditional memory control program compared to the data clearly has a lower latency, which helps improve the overall performance of computer systems. AMD was the first memory controller on the desktop platform will be integrated in the CPU of Intel new Core Duo processor family also integrate the memory controller
CPU integrated memory controller inside the advantage is that we can effectively control the memory controller operates in CPU core with the same frequency, and because memory and CPU without going through the data exchange between the North Bridge, can effectively reduce the transmission delay. Analogy, it is like to move the goods directly to the warehouse next to the processing plant, greatly reducing the raw materials and finished goods warehouse and processing plant in the round-trip transportation between the time required, greatly improved production efficiency. As a system overall performance has improved.

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Knowledge: Computer switch err r analysis!

Sep.02, 2011 inUncategorizedComments Off

[Performance] boot failure normal self test is complete, there “DisketteBootFailure” message, can not enter the system. [Failure Analysis] appear in the message, because the boot floppy disk for errors, cause the system fails to start, as long as the replacement boot disk in the floppy drive to start the system. [Troubleshooting] to resolve the failure, the system starts normally, according to the following steps. ⑴ If the machine does need to boot from the floppy, then use a normal boot disk to replace the damaged boot disk, restart the computer. ⑵ In other cases, the user forgot to use the floppy disk out, and the CMOS and set the floppy drive as primary boot device. In this case, restart the computer an error message will appear, this time only the floppy disk out and press the Enter key to start the system from the hard drive. ⑶ order to avoid future recurrence of similar situations in the CMOS settings into “BIOSFEATURESSETEP” setting option, move the cursor to “BootSequence”, press the “PageDown” or “PageUp” key is set to start “C, CDROM, A “(that is, the C partition, floppy drive and select the boot device order). Then press “F10″ key to save and exit, restart the computer. [Show] the machine POST failure occurs after “Master (\ Slave) None” message, can not enter the system. [Failure Analysis] with an IDE data lines to two IDE devices must be correctly set the primary slave, or there will be “Master (\ Slave) None” error. [Troubleshooting] to resolve the failure, in accordance with the following steps. ⑴ check the data line two IDE devices (such as hard disk or CD-ROM), according to the prompts on the device, two devices were set as master and slave, restart the computer. ⑵ IDE device jumper setting need to pay attention, start with an IDE hard line should be set for the main equipment, or system to not start. [Performance] POST failed, the emergence of “Harddisk (s) drivefail” message, you can not normally enter the system. [Failure Analysis] we can see from the error message is hard disk malfunction, leading to not start the system. May be due to the hard disk is not connected properly, or because of problems with the hard disk itself. [Troubleshooting] To solve the hard disk failure, through the following solutions. ⑴ check the hard drive data interface, data interfaces to ensure that no damage, and carefully check the hard drive power connector, check for loose power. ⑵ exclude the data and power interface problems, if the fault is still not resolved, you will need to drive to get the other machines tested to determine whether the fault for the hard disk itself. [Performance] system startup self-test failure, the emergence of “BIOSROMChechsumerror, Systemhalted” error message, unable to enter the system. Restart the system again, there is still the same error. [Failure Analysis] the message that the BIOS check error is found, it may be due to BIOS update failure or accidental damage caused by the motherboard BIOS. Actually received sacrificial victim wash hate Ken paternity Guo gingival dream trip Di pepper sand barrier Minato umbrella ㄍ BU!? ⑴ If you have just to update BIOS, restart prompt will appear in the error message, the fault is likely to be a failure by the flash BIOS caused. Typically, the motherboard needs to be refreshed after the failure to the repair location specified by the manufacturer, unless the motherboard has dual-BIOS boot, you can refresh fails, start the system with a backup BIOS. ⑵ if the error is caused due to flash the BIOS, then it may be because the motherboard BIOS for some unexpected damage, in this case, also need to specify the location of the motherboard to the manufacturer for repair. [Performance] POST failed, the screen suddenly “CMOSchechsumerror-Defaultsloaded” error, and gives “PressF1continue, Deltoentersetep” message. [Failure Analysis] The error message the CMOS test error, and prompted to press “F1″ key to start the computer, or press “DEL” key to enter the CMOS setup program. This failure, mainly because the CMOS battery is low, leading to a serious configuration errors. [Troubleshooting] to resolve the failure, can be completed by the following method. ⑴ Follow the prompts, press “F1″ key to enter the default CMOS settings, the computer continues to boot into the system, and then restart the computer, check the fault elimination. ⑵ failure after you restart the computer if not eliminate, the interruption is not caused by the CMOS settings wrong. Is very likely because the CMOS battery problem or low battery, need to replace a new CMOS battery. [Performance] POST failed, the screen displays “CMOSSystemOptionsNotSet” information and can not enter the system. [Failure Analysis] The data stored in the CMOS damaged or missing, the error message will appear. Just enter the CMOS setup program to re-set accordingly, you can solve problems. ⑴ restart the computer, press the “Del” key to enter the CMOS setup program, select “LOADBIOSDEFAULT” option and press Enter. ⑵ in the pop-up prompt box, enter “Y”, then press the Enter key parameters into the CMOS default settings, rebooting. [Performance] [failure] POST screen every time “CMOSBatteryStateLow” error message, and gives “pressF1continue, orDELtosetep” message, press “F1″ key to enter the system properly. [Failure Analysis] the message that the CMOS on the motherboard used in battery is running out, to remind users to replace batteries as soon as possible. [Troubleshooting] to avoid a repetition of the message, according to the following solutions. ⑴ to buy a high quality CMOS battery, the CMOS battery on the motherboard replaced the original, restart the computer will no longer appear in the message. ⑵ If after some time, the message is still there, one could buy a battery is the problem. Another possibility is that the motherboard CMOS power supply circuit leakage phenomenon, which requires the board to the vendor maintenance. [Performance] boot failure, the prompt “CMOSChecksumFailure” information. [] CMOS failure analysis and processing parameters are saved will have a code value. This value is used for error checking, if the read value and the value does not match, then this error message. To resolve the failure, need to properly set up BIOS. [Performance] boot failure, the prompt “CMOSTime

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SPD and the bas cs of laptop memory recognition

Sep.02, 2011 inUncategorizedComments Off

The memory module specifications, developed by the JEDEC committee, please log in to http://www.jedec.org/ get more information? SPD is SERIAL PRESENCE DETECT abbreviation, in Chinese means the existence of serial test module. that is mentioned above by the IIC serial interface EEPROM on the memory slot of the module checks the existence of information. In this case, module related information shall be recorded in the EEPROM. Customarily, we Fengyun EEPROM IC called the SPD. But sometimes there is an error message read, say, some people find that their DIMM 2007 production date turned out to be 88 weeks, significantly, only 52 weeks a year it is not the software tools sucks? JEDEC standard given, in part, depending on the module? type defined, in part, manufacturers own definition, this part can not fill even so, a considerable part of the data is uncertain, or even not defined, then access the content of these EEPROM, it may explain the error. we look at all concerned about the data to see where they are in Figure 3 byte 03 ~ 06, there is byte 13, these data mean, one-sided 8-chip memory, the capacity of single-chip 256Mbit, so you can figure out?? This is the root of the memory of a total of 256MB. SPD byte 18 in the module can be given in this work the CL value. See byte 12h, the value 0Ch, meaning it can support CL = 2.5, 2 species. in front of byte 09 frequencies, it must be the maximum that is working in the CL on CL = 3, while working in the CL = 2, frequency is how much? to check byte 23, which in Figure 3 byte 17h, the value is 75h, that is 7.5ns, corresponding to 133MHz SPD information is not information, but read the chipset in the message that is another story.. If you read the old version of the software with the new value read is not the same, please a new version shall prevail, because the author may not have the software update to the new chipset release. chipset development speed faster than the JEDEC standard more:) about a fun thing, some of the IC is used to support DIMM PC133, but PC100 is the content of the SPD, which occurred mainly in companies like IBM, which is why? Some products, such as TP600E not Support PC133 and support PC100, but SODIMM suppliers may only be taken? to the PC133 IC, taking into account the IC is compatible with PC100, then, the SPD content written PC100, with the sale of accessories for the factory to avoid confusing users.

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Spectrum analyzer ypes and applications

Aug.24, 2011 inUncategorizedComments Off

Spectrum Analyzer (SpectrumAnalyzer) is used to display the frequency domain characteristics of the input signal spectrum, so the signal analysis is indispensable in terms of measurement instruments. Spectrum analyzer through a frequency domain signal analysis, research, and also used in more different areas, such as wireless signal transceiver, signal interference detection, spectrum monitoring, and device characterization, etc., is engaged in electronic product development, production test commonly used tool, especially for wireless communication signal measurement tool is necessary, it is widely used, it is also known as RF engineers to the measurement of the multimeter. Its main features include: frequency setting, reference level set tracking generator set, tracking control settings, the use of tagging measuring return loss, and bandwidth, scan time and trigger control settings and other functions.
in the time domain signal for measurement, the oscilloscope is a very important and very effective measuring instruments, it can directly display the signal amplitude, frequency, period, waveform and phase changes such as the response . In general, the oscilloscope must have two-track output display device, while a built-in IEEE-488, IEEE-1394 or RS-232 and other interface functions to link with drawing instruments, and conducive to follow-up measurements and drawings display information output study comparison. Only disadvantage is confined to low-frequency oscilloscope signal for high-frequency signal analysis has become a major challenge.
advantage of the spectrum analyzer, is the oscilloscope is to make up for the lack of high-frequency signal analysis, and while the multi-frequency signal to frequency-domain approach to present to facilitate the identification of the different frequencies of power device, and display the signal in the frequency domain characteristics.
at immediate domain measurements and frequency domain measurements of the different
spectrum analyzer types
spectrum analyzer (SpectrumAnalyzer) is used to display the input signal frequency domain spectral characteristics. And based on differences in signal processing is divided into two types, namely, real-time spectrum analyzer (Real-TimeSpectrumAnalyzer), and scan tuning spectrum analyzer (Sweep-TunedSpectrumAnalyzer) and other two.
real-time spectrum analyzer can be displayed at the same time frequency domain signal amplitude, its working principle is set for different frequency signals corresponding to the filter and detector device (Detector), and by the simultaneous multi- work scanner signal output to the screen, is its ability to display periodic stray wave (PeriodicRandomWaves) transient response, but the drawback is expensive, and the bandwidth range, the filter and the maximum number of multi-exchange time (SwitchingTime) would restrict its performance.
scanner tuned spectrum analyzer is the most common type of spectrum analyzer, and its basic structure and a similar superheterodyne receivers, mainly works through the attenuator input signal directly into the mixer device, the tunable local oscillator synchronized by a CRT screen at any time scanner generator produces a linear change of the oscillation frequency of inter-cropping, then mixer and mixing the input signal after the down-wave frequency signal (IF) amplification, filtering and detection sent to the CRT screen, so the longitudinal axis of the CRT screen display signal amplitude and frequency of the relative relationship.
As mentioned above, affecting the signal response of the key for the filter bandwidth. Gaussian filter (Gaussian-ShapedFilter) influence function is common to measure the resolution bandwidth (ResolutionBandwidth; RBW). RBW represents the meaning of two different frequency signals can be clearly distinguish the difference out of the minimum bandwidth, so the two signals of different frequencies lower than if the bandwidth spectrum analyzer resolution bandwidth, so the overlap of two signals will can not tell. This seemingly lower RBW will help distinguish between signals of different frequencies and measurement work, however, there may be too low RBW high frequency signal to filter out, resulting in signal distortion when the display. Higher RBW certainly help broadband signal measurements, but it may increase the noise underlying value (NoiseFloor), reduce the measurement sensitivity, and low-intensity signals for detecting prone to obstruction. Distortion value and set the RBW is closely related, so set the appropriate width RBW spectrum analyzer is the correct use of key concepts.
In addition the traditional spectrum analyzer front-end circuit is tunable within a certain bandwidth of the receiver. When the input signal frequency by frequency, by low-pass filter output and filter the output value is the vertical component, as the frequency is the horizontal component, so the screen coordinates on the map is presented by the input signal spectrum. Because the frequency can reach a very wide frequency (eg, from 30Hz ~ 30GHz), and with an external mixer, but can be increased to more than 100GHz, the frequency spectrum analyzer is the widest coverage of measuring instruments, whether measuring continuous signal or modulated signal, the spectrum analyzer is ideal measurement tool. Only the traditional spectrum analyzer has the disadvantage that it can only measure the frequency range, but the lack of phase information, so the nature of the instrument is not part of the scalar vector instruments.
new generation of spectrum analyzers is based on Fast Fourier Transform (FFT) measurement instruments. By computing the Fourier components of the measured signal decomposition established frequency components, thus achieving the traditional spectrum analyzer with the same results. The new spectrum analyzer using digitally, directly from the analog / digital converter (ADC) sampling the input signal, and then by computing the Fourier spectrum obtained after treatment distribution.
In today measurements, no matter what signals can be measured in many ways. The most basic instruments commonly used are the oscilloscope to observe the signal waveform, frequency and amplitude and so on. However, due to changes in the signal is very complicated, a lot of information with the oscilloscope can not be detected, for example, if you want to analyze a non-sinusoidal signal, in theory, it is a different frequency and voltage vector of the superposition. The perspective of the analysis, oscilloscope horizontal axis represents time, vertical axis for the voltage amplitude, the curve is that time-varying voltage waveform, which is the time-domain measurement method. If you want to observe the frequency component, must be frequency-domain method, the abscissa is the frequency axis for the power range. This can be seen at different frequencies on the power distribution range, we can understand these signals of spectrum. With a single signal spectrum, then the signal can continue to reproduce and replicate the complexity out of this for signal analysis is very important.
When a digital signal contains many video and audio signals, and its spectral distribution will be quite complex. In the satellite monitoring, these signals must be analyzed from the perspective of the spectrum to obtain the required parameters. There are two ways to analyze the frequency of the signal. The first is the collection of time-domain signal, then its Fourier transform, convert it into a frequency domain signal, this method is called dynamic signal analysis. Feature is relatively fast, have a higher sampling rate and high resolution. Even the two signals very close intervals, using Fourier transform they can be distinguished. However, with digital sampling and analysis, the maximum frequency that can be analyzed by its sampling rate, constraints on high-frequency signal analysis. Therefore, the analysis of the highest frequency only about 10MHz, so the range is part of the vector analysis. Such analysis methods are generally used for low-frequency signal analysis, such as sound and vibration. Another approach is to rely on the principle of hardware circuit, rather than through mathematical equations conversion. It can directly receive signals, such as analytical instruments tuned superheterodyne receiver directly scan analyzer, which is the above mentioned scan tuning the spectrum analyzer.
spectrum analyzer applications
spectrum analyzer main function is to measure the size or amplitude of the signal, and its wide range of applications, including system maintenance, signal measurement, group pieces of material gain and the frequency of quality control, etc., in the spectrum analyzer into the scope of application.
amplifier gain, frequency response characteristics of passive components and measurement
cable television and communications system using a large number of amplifiers and splitters (Tap), connectors, coaxial cable and other passive components, component quality will affect the quality characteristics of the signal, so the pre-screening will help to ensure signal quality. For example, through the spectrum analyzer tracking generator to evaluate the object under test (DUT) frequency response characteristics, measurement of results by the drawing instruments (Plotter) output and access to information. Measurement frequency range can be pre-set time, and time to obtain the corresponding curve, and so will be significantly reduced in the past through the oscilloscope and function generator according to different frequencies must be measured point by point the complicated operating procedures.
own spectrum analyzer tracking generator (TrackingGenerator) function to generate scanning signals transmitted by the DUT to the spectrum analyzer RF receiver, the frequency response from the DUT and measuring the response of the short wiring mutual comparison, can come to the DUT insertion loss (InsertionLoss), the same way as other related components will be available in the frequency response measurements. distortion measure

measured by the Fourier equation may be that, in addition to undistorted resonance wave (sine wave), the waveform in addition to any basic waves, are also high harmonic wave components, such as periodic sawtooth (PeriodicSawtoothWave), etc., started by Fourier equation, which corresponds to the mathematical display an unlimited number of harmonic style, and harmonic components in the spectrum analyzer can be clearly demonstrated.
oscilloscope can not detect the signal distortion and can only show the signal waveform and time relationship, but the spectrum analyzer from the corresponding harmonic spectrum, can accurately assess the harmonic signal and the signal amplitude, and then assess the distortion of Colonel

communication monitoring wireless communications requirements for spectrum use, you must use high-frequency, and send and receive signals through antennas, antenna with a spectrum analyzer through it is easy to detect the current signal strength and carrier communication frequency, such as using directional antennas, two sets of measurement equipment will be able to identify the source, which is relevant to ban illegal radio units (such as illegal underground radio stations), the main detection technologies .
based on the need to scan the spectrum analyzer bandwidth appropriate adjustments, such as zoom in or out, fine-tuning in order to assess the interference signal by measuring regional conditions, this method can be used as a design regional communication station or kinds of mobile communication system base station reference. By the directional antenna to adjust the amount of the measured maximum signal amplitude can be determined by the directional antenna, the signal source direction, if another group with the adjacent monitoring devices, from the intersection of two antenna signals can be obtained source position, immediately detects that the location of emission sources, in this way, through more sets of measurements will be accurate emission source.
cable television image information measurements
cable TV (CATV) coaxial cable or fiber optic cable through the cable to send video to other users at home. The development of technology, in order to reduce road digging construction of the difficulty of laying cables and reduce costs, manufacturers have proposed an open microwave or by satellite to the point (Spot) means the signal sent to the user at home, currently has in North America service provider for Northern California customers launch video channel has 150 satellite signals. Therefore, cable, microwave and satellite transmission of video approach has been applied to co-exist on the market, providing customers a wider variety of viewing options.
CATV system main function is to transmit video programming and data, and maintain the normal operation of the system, the transmission about 100 or more video channels, as well as information retrieval user terminals timely response to control signals, etc. two-way interactive services and other functions. In the CATV system includes a wide variety of video signals, such as voltage and current amplitude, gain, frequency and power, etc., which gain power mostly on the values ??that the. The RF signal amplitude, frequency can be general instruments (such as an oscilloscope) measured the amount of the signal phase (Phase) by the vector oscilloscope (VectorScope) measurement, the so-called vector oscilloscope is a very stable time base oscilloscope ring, can be used to check time delay between two signals. The spectrum analyzer is indispensable for CATV signal measurement electronic equipment.
antenna characteristics measurement
In addition to the spectrum analyzer measured the amplitude of the signal strength in the air outside, as long as with the bridge (Bridger) also measured the energy reflection loss (Returnloss ). As the popularity of mobile phones, the number of base stations in the city quite a number of concerns due to electromagnetic radiation has been plagued by injuries the user, so the electromagnetic wave intensity measurement has been increasingly the attention of members. Spectrum analyzer for the antenna can be any space electromagnetic radiation intensity or strength measurements.
use of spectrum analyzers for measuring
can be measured with unpredictable or not, depends entirely on the spectrum analyzer settings. This includes the attenuation, frequency range and resolution bandwidth setting. Spectrum analyzer settings including frequency range, resolution and dynamic range, dynamic range and the maximum input power that is involved in burning power gain compression to less than 1W of input signal once the work area will appear over the linear error. In addition, sensitivity is also considered a spectrum analyzer to the input signal can be measured whether or not the key.
parameters observed frequency range from two aspects, first, whether the setting of the frequency range narrow enough to have sufficient frequency resolution capability, which is enough to narrow the sweep width. The second is whether there is sufficient frequency range width can measure to the second and third harmonics. When using a spectrum analyzer measuring harmonic distortion when the amplifier if the amplifier at 1GHz, it the third harmonic is 3GHz, which is to consider the frequency range of the maximum measurable width. If the spectrum analyzer is 1.8GHz, it can not be measured, if the spectrum analyzer is 26.5GHz, can be measured to its third and fourth harmonics.
-resolution spectrum analyzer is a very important parameter. Resolution means that when two frequencies to be measured when the power is not the same, they must be separate. Wide will frequently set in three different widths, the following is the corresponding bandwidth settings see curve. Frequently in the more narrow the width of the higher resolution, the wider the width is frequently lower resolution. Resolution bandwidth directly affects the small signal recognition and measurement results.
This paper briefly describes the application of the spectrum analyzer and operation in many applications, the spectrum analyzer is a good helper engineer. The best spectrum analyzer is determined by many factors and parameters, requiring overall consideration, rather than the pursuit of the perfect single indicator, the basic elements of various types of analysis and measurement, in order to achieve more perfect measurement results .

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To see how companies ch ose bi dunkin

Aug.24, 2011 inUncategorizedComments Off

dunkin company managers have a clear goal. They need a single central repository of resources, need to find data fast track and compare the use of these data to calculate the consideration to support the company strategic analysis … … With the dunkin become the world has 12,000 retail branches brand, its business intelligence system trouble. it has to dunkin director of strategy rickbroughton CIO michael furlow company had reported that he and Business Intelligence experts steve allocco the pebble beach at the meeting this week are strongly recommended their company successful case studies. The meeting by the CIO Council and searchcio. Com website co-sponsored, and 175 senior staff to participate in it. dunkin company decided to implement a business intelligence project, need to match the received data to better understand their products, dealers and customers. allocco more proficient in business intelligence systems, and business intelligence advisory committee in charge. The committee is cross-sectoral cooperation from the project developed from research institutions, mainly the members of his department to provide it feedback and development strategy. dunkin company goal is to create a perfect database system, which includes better product sales and the background of the cause and conditions. dunkin UK domecq is a member of the joint companies, the combined companies are pernod ricard sa week price of U.S. $ 7.4 billion acquisition. In 2004, dunkin rands the company reached a record 4.8 billion dollars in sales. larry lotenero is a clinical research organization ucsf medical information research center director, for him, dunkinbrands the company business intelligence cases in the importance of data accuracy to give him a good lesson. lotenero companies now are starting a big business intelligence project, he said, is the accuracy of the data should first pay attention to the problem. The project is very huge amount of data about have 10 – 12 trillion megabytes of data. These data swallowed a large number of resources. alloco said, lotenero formed a team for business intelligence, and thus along the correct path. it Union in their presentation of information to encourage the development of the organization by executives real business intelligence. Many people have a greater emphasis on commercial interests, executives who did not need to shout; the support of major manufacturers will increase a project credibility. At the same time, their success also stressed the importance of short-term, rapid creation of landmark results. This strategy will be attracted actors and users. dunkin company managers have a clear goal. They need a single central repository of resources, need to find data fast track and compare the use of these data to calculate the consideration to support the company strategic analysis. Today companies use several different manufacturers of the technology to support its business intelligence platform, which manufacturers include oracle company, blue cube hyperion company and the company. For an organization, such as replacement of a new business intelligence systems such important changes, those who need to perform to the manufacturer complex team work together. Is allocco called “multi-functional business team life cycle” strategy means that dunkin business intelligence development team over time and continuous evolution. dunkin company has trained about 150 users of the system, and plans to add 50. The new system may cause them to fall behind or be phased out. Business intelligence applications data requirements of today organizations the primary system, which enables organizations to make decisions closer to the truth. The application of large volumes of data about 1.2 terabytes. allocco said, “We can measure the inner half an hour a specific number of areas we have been selling espresso;” and can compare the two store sales, and so on. You have questions about this article? Do you have any technical Confusing? Do not hesitate to click the button below, and our experts will help you.

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Rhetoric such as sales d ta cloud sitting destroy Huanglong!

Aug.24, 2011 inUncategorizedComments Off

● U.S. retailer a few happy tears? Economy under the weight of American consumers have become so cautious consumer spending, government data showed U.S. consumers to reduce the use of credit card number. In mid-October the United States, large and small retailers have issued unsatisfactory sales performance. The largest U.S. clothing retailer Gap announced that its September same-store sales fell 11%, its T. J. Maxx, Marshalls, and A. J. Wright and other chains of TJX and its competitors RossStores also announced the 9 accident same-store sales decline of news. Abercrombie

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Ten thousand new products while starting Tmall starting to create new history of the catt e

Aug.16, 2011 inUncategorizedComments Off

Brief content: August 15, Taobao Mall (Tmall.com) announced a joint one hundred kinds of brand also released new, up to 10,000 new fall merchandise goods will gather TMALL, involving women men , sports outdoor, footwear and luggage, beauty fashion and other industries. JACK

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Hyundai HY-20 II stereo 77 yuan crazy half sales

Aug.16, 2011 inUncategorizedComments Off

Hyundai HY-203II is a basis in the HY-203 and 2.1 higher on large sound, its more cool than the old models, all-black appearance, the main volume knob using bright silver technology. In the hot summer months, the modern HY-203II sound can be described as half-price sales price chill wind in at 15 o lock on August 12, you can only spend 77 yuan Taobao official in the modern mall hyundai Shenzhen stores (http:/ / hyundaisz.tmall.com) on the purchase of this machine. And there are more modern sound one dollar spike, value special activities waiting for you!
From the exterior, modern HY-203II audio compact fashion, excellent workmanship, black square wooden box, PVC veneer to ensure a good feeling. Subwoofer with a personalized front-end inverted square hole design, with holes down the top and a red indicator light and built-in volume knob, there is a circle surrounding the audio scale knob, adjust the quick and easy. The back of the subwoofer also designed a separate gain knob, you can effectively enhance the bass performance, there will be a good rock music playback performance.
from the configuration point of view, the modern HY-203II rated audio output power of 10W, the speaker in using a 4-inch woofer and 3-inch-wide band units, and uses a magnetic processing, user placed at random. Woofer is set in the main box at the bottom, thereby greatly enhancing the low amount of sense. Hyundai HY-203II stereo sound quality quite satisfactory performance, frequency response range is 35Hz-18kHz. 3.5mm stereo interfaces to meet the requirements of entry-level listening.
From the quality point of view, are HY-203II internal circuits used in all modern electronic control circuit and the original imported audio chip, advanced electronic frequency technology, the overall Magnetically shielded, the speakers when playing music, the sound quality on the reproduction of the original sound to the sense of hearing and, in order to improve bass performance, to make up for lack of small-diameter bass units, the main modern HY-203II-ground tank with a booster design, the bass control button is also designed to back. This makes the sound quality is more strongly layered, soft and sweet tone, powerful bass, can create more good acoustic environment, such as speakers, no wonder they are so angry.

beautiful fashion appearance, law-abiding, sound, low price, much to cool the hot summer months. Recent want to buy Hyundai HY-203II users can go to modern audio sound Taobao Mall hyundai Shenzhen official store see what! Share: microblogging striving to become the first person to broadcast space friend microblogging:
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