Distributed minimum mean-square error interference rejection combining (MMSE-IRC) processing for radio access networks

One or more non-transitory computer-readable media (NTCRM) having instructions stored thereon, that when executed by one or more processors cause a baseband unit (BBU) to:

• receive a processed signal from a remote radio unit (RRU) after a first phase of processing that includes maximum ratio combining (MRC) of a modified extended channel, wherein the modified extended channel includes a received signal on a channel of one or more user equipments (UEs) served by the RRU and interference samples that correspond to other cells or additive noise are scaled by a scaling coefficient;
• perform a second phase of processing on the processed signal to generate an output signal, wherein the second phase includes regularized zero forcing, wherein the second phase of processing includes a first matrix inversion based on the interference samples and a second matrix inversion based on the channel of the one or more UEs, and wherein the first matrix inversion is performed with a larger granularity in the time or frequency domain than the second matrix inversion;
• and
• provide the output signal to a signal decoder to decode data in the output signal.

An apparatus to be implemented in a remote radio unit (RRU), the apparatus comprising:

• radio frequency (RF) interface circuitry;
• and
• processor circuitry coupled to the RF interface circuitry, the processor circuitry to:
• receive, via the RF interface, a signal associated with an extended channel that includes a channel of one or more user equipments (UEs) served by the RRU and interference samples that correspond to other cells or additive noise;
• scale the interference samples by a scaling coefficient to obtain a modified extended channel;
• perform maximum ratio combining (MRC) based on the modified extended channel to obtain a processed signal, wherein the processed signal has fewer elements than the received signal associated with the extended channel;
• quantize the processed signal to obtain a quantized signal, wherein a number of quantization bits in the quantized channel is based on a value of the scaling coefficient;
• and
• transmit the quantized signal to a baseband unit (BBU) via the RF interface circuitry.

One or more non-transitory computer-readable media (NTCRM) having instructions stored thereon, that when executed by one or more processors cause a remote radio unit (RRU) to:

• receive a signal associated with an extended channel that includes a channel of one or more user equipments (UEs) served by the RRU and interference samples that correspond to other cells or additive noise;
• scale the interference samples by a scaling coefficient to obtain a modified extended channel;
• perform maximum ratio combining (MRC) of the received signal based on the modified extended channel to obtain a processed signal;
• and
• transmit the processed signal to a baseband unit (BBU) via a fronthaul link;
• wherein the processed signal is quantized before transmission to the BBU, and wherein a number of quantization bits in the processed channel is based on a value of the scaling coefficient.

One or more non-transitory computer-readable media (NTCRM) having instructions stored thereon, that when executed by one or more processors cause a baseband unit (BBU) to:

• receive a processed signal from a remote radio unit (RRU) after a first phase of processing that includes maximum ratio combining (MRC) of a modified extended channel, wherein the modified extended channel includes a received signal on a channel of one or more user equipments (UEs) served by the RRU and interference samples that correspond to other cells or additive noise are scaled by a scaling coefficient;
• receive, from the RRU, an indication of one or more parameters used by the RRU for the first phase of processing, wherein the one or more parameters include the scaling coefficient;
• perform a second phase of processing on the processed signal to generate an output signal, wherein the second phase includes regularized zero forcing, and wherein the second phase is performed based on the one or more parameters;
• and
• provide the output signal to a signal decoder to decode data in the output signal.