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Single User and Multi User MIMO codewords in LTE

Single User and Multi User MIMO codewords in LTE Figure shows how the two codewords are used for a single user in the downlink. It is also possible that the code words to be assigned to different users to create multi-user MIMO (MU-MIMO). Depending on the channel information available in the eNB, modulation and precoding … Read more

What is Cyclic prefix in LTE ?

The guard period after each rectangular pulse carrying the modulated data symbol is a simple and efficient method to deal with multi-path reception. The cyclic prefix (CP) simply consists of the last part of the following symbol. The size of the cyclic prefix field depends on the system and can even vary within one system. … Read more

Vocoders and its Type in CDMA

Vocoders Human voice is made up of a combination of voiced and unvoiced sounds Vocoders exploit these properties of speech production mechanism Vocoders do not respond to music, non-human sounds and tones from voice band modems PCM vs VOCODERS CDMA VOCODERS 8 kbps variable rate coder Rate 1 Rate 1/2 Rate 1/4 Rate 1/8 Cdma … Read more

Guard Band Requirement in LTE

Here I write on simple how guard band requirement for LTE for 2 option. Guard band requirement LTE verses GSM and guard band requirement LTE FDD verse LTE TDD Guard Band Requirement: LTE-FDD vs GSM/UMTS Configuration is simpler for FDD based systems because both LTE FDD and its neighboring technologies are based on frequency duplex … Read more