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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).

Linked Answer Records

Master Answer Records

Answer Number Answer Title Version Found Version Resolved
33266 LogiCORE 3GPP LTE MIMO Encoder - Release Notes and Known Issues N/A N/A

Associated Answer Records

AR# 38684
Date Created 11/08/2010
Last Updated 12/15/2012
Status Active
Type General Article
  • 3GPP LTE MIMO Encoder