High BER,BLER,DBLER measured in CMU200 results in GSM,GPRS test failure

BER,BLER and DBLER are basically performance measurements carried out in GSM and GPRS system. The standard defines pass and fail criteria for BER/BLER/DBLER at various SNR for traffic(TCH) and data channels (PDTCH or PDCH).

The different modulation schemes of GPRS such as CS1,CS2,CS3 and CS4 will have different limits. Also EGPRS modulation-coding schemes such as MCS1,MCS2,MCS3,MCS4,MCS5,MCS6,MCS7,MCS8 and MCS9 will have different limits specified in the 3GPP standard as mentioned below.

BER stands for Bit Error Rate, BLER for Block Error Ratio and DBLER for Data Block Error Rate. Refer page on BER vs BLER vs DBLER for details on these parameters.

BER = Erroneous bits / total number of bits x 100%
BER II = Erroneous class II bits / total number of class II bits x 100%
BER Ib = Erroneous class Ib bits / total number of class Ib bits x 100%
FER (Frame Erasure Rate) = Erroneous frames / total number of frames x 100%

BLER = Blocks received in error / total number of blocks x 100%
DBLER = Blocks with erroneous data fields / total number of blocks x 100%
USF BLER = Assigned USFs received in error / total number of blocks x 100%
False USF Detection = Unassigned USFs received in error / total number of blocks x 100%

BER Limit

TCH/FS, class II will have limits as specified below:
Under static channel conditions, BER should be <= 10^-4
Under EQ50 channel conditions, BER <= 3%

This should be maintained till input level of -40 dBm under static as well as multipath channel environments. BER of 10^-3 need to be maintained till level of -15 dBm for GSM-900 band and -23 dBm for DCS-1800 band.

The above BER specification should vary with respect to receiver sensitivity level.
For DCS-1800 class 1 or class 2 MS the limit is -100 dBm.
For DCS-1800 class 3 MS it is -102 dBm.
For GSM-900 and for small MS it is -102 dBm

GSM 05.05 Version 5.0.0 standard specifies various FER/BER limits for various channel types such as TCH/HS,TCH/FS and so on. For exact limits under various channel conditions go through the table 1:Reference sensitivity performance.

BLER Limit

The BLER rate must be less than or equal to 10% for various GSM bands such as GSM 400, GSM 700,GSM 850, GSM 900, DCS 1800 and PCS 1900. The limit is specified in Release 99 GSM 5.05 specifications.

Test and Measurement Equipments

This section covers test and measurement equipments for WLAN, WiMAX, zigbee, Bluetooth, GSM, UMTS, LTE and more standard based device testing. It covers spectrum analyzer, VSG, VSA, frequency counter, protocol analyzer, AWG, digitizer, function generator, pulse generator, RF network analyzer, power meter, logic analyzer and more.
Test and Measurement Equipments BER Testing equipments Agilent T & M Solutions Anritsu T & M Solutions Rohde & Schwarz T & M solutions wireless channel emulator Vector signal generator Vector signal analyzer Power Analyzer Equipments Protocol Analyzer

RF and Wireless Terminologies