US 12,438,578 B2
Method for enabling efficient MIMO processing for O-RAN fronthaul interface in cloud RAN systems
Wessam Afifi Ahmed, Plano, TX (US); Sung Joon Maeng, Raleigh, NC (US); Young-Han Nam, Plano, TX (US); and Sridhar Rajagopal, Plano, TX (US)
Assigned to Mavenir Networks, Inc., Richardson, TX (US)
Filed by MAVENIR NETWORKS, INC., Richardson, TX (US)
Filed on Jul. 15, 2021, as Appl. No. 17/376,505.
Claims priority of provisional application 63/053,967, filed on Jul. 20, 2020.
Prior Publication US 2022/0021423 A1, Jan. 20, 2022
Int. Cl. H04B 7/0456 (2017.01); H04B 7/0452 (2017.01); H04L 5/00 (2006.01); H04W 72/21 (2023.01)
CPC H04B 7/0456 (2013.01) [H04B 7/0452 (2013.01); H04L 5/0048 (2013.01); H04W 72/21 (2023.01)] 2 Claims
OG exemplary drawing
 
1. A method of optimizing an uplink massive multiple input, multiple output (mMIMO) combining operation in an Open Radio Access Network (O-RAN) fronthaul interface between O-RAN radio unit (O-RU) and O-RAN distributed unit (O-DU), comprising:
splitting an uplink (UL) massive multiple input, multiple output (mMIMO) combiner into i) an O-RU combiner for the UL mMIMO residing in the O-RU and ii) an O-DU combiner for the UL mMIMO residing in the O-DU;
compressing, at the O-RU combiner, a first number of received signal streams and associated demodulation reference signal (DMRS) symbols from multiple antennas to a second number of signal streams and associated streams of compressed DMRS less than the first number of the received signal streams;
sending, by the O-RU combiner, the compressed second number of signal streams and associated streams of compressed DMRS to the O-DU via the fronthaul interface;
generating, at an MU-MIMO combiner generator of the O-DU, an MU-MIMO combiner matrix based on the streams of compressed DMRS;
sending, by the O-DU combiner, the generated MU-MIMO combiner matrix based on the streams of compressed DMRS to a O-RU combiner buffer;
implementing, at the O-DU combiner, multiuser, multiple input, multiple output (MU-MIMO) combining by applying the MU-MIMO combining matrix to the compressed second number of signal streams; and
reducing, by the O-DU combiner, the output streams of the MU-MIMO combining at the O-DU combiner to the number of users streams.