System and method for uplink coordinated transmission in an open radio access network

Abstract

A communication system having to an open radio access network architecture, the communication system includes a number (K) of user equipments configured to exchange messages through the communication system, the communication system comprising one or more radio unit and a distributed unit, each radio unit being connected to the distributed unit through a fronthaul link having a given capacity. The communication system comprises a coordination system being configured to coordinate the exchanges between the radio units of the system and the distributed unit, in response to a signal received by the radio units from a user equipment. The coordination system is configured to send a signalling message to each radio unit comprising data stream selection information, each radio unit comprising: a transformation unit configured to apply a transformation operation to the signal vector received by the radio unit, which provides a transformed vector, the transformation operation being defined to reduce the dimension of the received signal vector; a data stream selection unit configured to select a number of data streams corresponding to components of the transformed vector using the data stream selection information comprised in the signalling message, a quantizer configured to apply a quantization operation to the selected data streams, which provides quantized vectors, the radio unit being configured to send the quantized vectors to the distributed unit. The sum of the numbers of data streams selected at the radio units, over all the radio units of the communication system, is higher or equal to the product of the number of user equipments (K) and the number of antennas of a user equipment.