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AR# 38684

LogiCORE IP 3GPP LTE MIMO Encoder v2.0 - Release Notes/README for 3GPP LTE MIMO Encoder v2.0 rev 2 Patch -


This Answer Record contains the Release Notes for the LogiCORE 3GPP LTE MIMO Encoder v2.0 rev 2 Patch which deals with two issues

  • The inability to use the core with four antennas; Spatial Multiplexing, 16-bit data, 2 codewords, and 2 layers as defined in the LTE standard.
  • An issue when using codebook index 7, which results in the output on Antenna port 1 beingincorrect.


This Answer Record deals with two issues associatedwith theLogiCORE 3GPP LTE MIMO Encoder v2.0.

  • Issue 1: In the LTEspecification v8.7.0, Table (Codeword-to-layer mapping for spatial multiplexing) shows different combinations of layer and input code words for Spatial Multiplexing encoding. For 2-layer operation there are two options for the number of input codewords to use; 2 or 1. However, at present, the core can accept only one input codeword for 2-layer operation.Consequently, the D1 inputs (and D1 ready signal) are never asserted; see (Xilinx Answer 33852).
  • Issue 2: There is a problem with the core in that any encoding using the core and codebook index 7 likely shows errors. This would mean that the output on Antenna port 1isincorrect; see (Xilinx Answer 38290).

To allow operation with two input codewords and perform encoding using codebook, you need to install the patch described below:
  1. Before you install this patch, ensure that you have the following installed on your machine.
    NOTE: If you need any of the service packs, libraries, or IP Updates, you can obtain them from the Download Center at:
    • ISE 12.3i
  2. Download the 3GPP LTE MIMO Encoder v2.0 patch from:
  3. Extract the ar8684_3gpp_lte_mimo_encoder_v2_0_rev2.zip to a temporary directory so as to read the AR38684_3GPP_LTE_MIMO_Encoder_V2_0_REV2_readme.txt file for more information on whether to extract the zip file to %XILINX% installation directory or use MYXILINX environmental variable.

Patch Fixes
Issue 1
Issue: The core does not accept two input codewords for 2-layer operation.
Symptom: The D1 READY signal does not get asserted

Issue 2
Issue: The core encode correctly for codebook index 7.
Symptom: The output on Antenna port 1 is incorrect

For a detailed list of LogiCORE 3GPP LTE MIMO Encoder Release Notes and Known Issues,see (Xilinx Answer 33266).



Answer Number 问答标题 问题版本 已解决问题的版本
33266 LogiCORE 3GPP LTE MIMO Encoder - Release Notes and Known Issues N/A N/A


AR# 38684
创建日期 11/08/2010
Last Updated 12/15/2012
状态 Active
Type 综合文章
  • 3GPP LTE MIMO Encoder