Block Error Rate And Bit Error Rate
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a quality control measure with regards to how well audio is retained on block error rate vs bit error rate a compact disc over time. Block Error Rate (BLER) is block error rate in lte a ratio of the number of erroneous blocks to the total number of blocks received
Acceptable Bit Error Rate
on a digital circuit. Block error rate (BLER) is used for W-CDMA performance requirements tests (demodulation tests in multipath conditions, etc.). BLER is measured after
Bit Error Rate Measurement
channel de-interleaving and decoding by evaluating the Cyclic Redundancy Check (CRC) on each transport block. Block Error Rate (BLER) is used in LTE/4G technology to know the in-sync or out-of-sync indication during radio link monitoring(RLM). BLER (in LTE) = No of erroneous blocks / Total no of Received Blocks. Normal BLER bit error rate pdf is 2% for an in-sync condition and 10% for an out-of-sync condition. "Block Error Ratio (BLER) Measurement Description". February 28, 2014. Retrieved 23 December 2015. Retrieved from "https://en.wikipedia.org/w/index.php?title=Block_Error_Rate&oldid=696463547" Categories: Compact discDigital audio Navigation menu Personal tools Not logged inTalkContributionsCreate accountLog in Namespaces Article Talk Variants Views Read Edit View history More Search Navigation Main pageContentsFeatured contentCurrent eventsRandom articleDonate to WikipediaWikipedia store Interaction HelpAbout WikipediaCommunity portalRecent changesContact page Tools What links hereRelated changesUpload fileSpecial pagesPermanent linkPage informationWikidata itemCite this page Print/export Create a bookDownload as PDFPrintable version Languages Add links This page was last modified on 23 December 2015, at 09:17. Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. Privacy policy About Wikipedia Disclaimers Contact Wikipedia Developers Cookie st
How is a Block Error Ratio Measurement Made? 3GPP TS 34.121, F.6.1.1 defines block error ratio (BLER) as follows: "A Block Error Ratio is defined as the ratio of the number of erroneous blocks received to the total number of
Bit Error Rate Tester
blocks sent. An erroneous block is defined as a Transport Block, the cyclic redundancy check bit error rate calculator (CRC) of which is wrong." To perform a block error ratio measurement, you must be on a Radio Bearer Test Mode call. The bit error rate tester software block error ratio measurement can be performed for both Symmetrical RMCs and Asymmetrical RMCs . For RMCs with a downlink rate of 12.2, 64 or 144 kbps, the test set sends a block every 20 ms. For https://en.wikipedia.org/wiki/Block_Error_Rate RMCs with a downlink rate of 384 kbps, the test set sends a block every 10 ms. The data sent on the downlink is determined by the DL DTCH Data setting. Symmetrical RMCs For Symmetrical RMCs (which use Transparent Mode (TM) RLC entities on the DTCH), the test set measures block error ratio by sending data and CRC bits in the downlink transport blocks to a UE that is configured in loopback mode 2 http://rfmw.em.keysight.com/rfcomms/refdocs/wcdma/wcdma_meas_wblerror_desc.html (UE Loopback Type must be set to Type 2 ). The UE then loops the data bits and CRC bits from the downlink transport blocks into the uplink transport blocks and transmits them in the uplink. The test set then generates a CRC from the data bits received in the uplink transport block and compares this calculated CRC against the CRC received in the uplink transport block (this CRC is the downlink CRC for the downlink transport block, looped back up by the UE). If the CRCs do not match, the transport block is defined to be a "block error." To perform the block error ratio measurement for symmetrical RMCs, Uplink DTCH RMC CRC Presence must be set to Used for Data . This disables the uplink CRC, to allow room for the UE to loop back the downlink CRC for each block (there are an equal number of available bits in the uplink and downlink, if the UE were to transmit an uplink CRC, it would not be able to loop back the downlink CRC). Asymmetrical RMCs For Asymmetrical RMCs (which use Acknowledged Mode (AM) RLC entities on the DTCH), the test set increments the Block Error Count when it receives a retransmission request from the UE. (The UE generates a CRC from the data bits received in the downlink
any of those wireless products. Let’s get a quick review about what they mean and what performance they indicate exactly. BLER stands for Block Error Rate while BER is Bit Error Rate. Here block means transport blocks and bit http://blog.pzheng.me/2014/10/20/ber-and-bler/ is information bits. Both BER and BLER are statistic results over a certain period. The Bit Error Ratio is defined as the ratio of the bits wrongly received to all data bits sent. The bits are the information bits above the convolutional/turbo decoder. A Block Error Ratio is defined as the ratio of the number of erroneous blocks received to the total number of blocks sent. An erroneous block is defined as a Transport error rate Block, the cyclic redundancy check (CRC) of which is wrong. Here comes a simple flow chart of decoding downlink DPDCH on UE side. As you can see, BLER measurement takes place at “CRC detection” phase within BTS physical layer. And BER is measured after CRC detection (most often in RNC) when information bits are received and then compared with an already-known data pattern. The pattern could be either fixed data or PN9/PN15. Of course pseudo bit error rate noise patter is preferred. In above figure, there is also a “DPDCH BER measurement” which is mainly used in internal R&D. This BER is measured by physical layer. Once the data is decoded, physical layer would encode the data and compare it with the original received data from RAKE receiver to calculate DPDCH BER. BLER indicates the quality of the whole network which is more critical. Because even there is data loss/error during transmission, the original data could be restored to perfect due to coding gain of turbo/convolutional algorithm. Thus BER just reflects the estimation of coding gain. Usually, in laboratory, we expect zero BER for each channel during low/medium-load testing. And pass criterion for BLER depends on different services and their QoS(Quality of Service). Outer Loop Power Control could help to maintain the BLER target. If BER/BLER doesn’t meet the criteria, we need firstly to fine-tune the test environment. If the test environment could be excluded from suspicion, for BER issue, we can compare the sending and receiving data to check whether they follow the same pattern. For BLER issue, we can start from debugging CRC functionality and then check from top to bottom to find the root cause step by step. In such way, we have found an undermining bug which caused the CRC data was different during retransmission. « Mod