Reduced Hardware Complexity Receive Antenna Subarray Formation for MIMO Systems Based on Frobenius Norm Criterion

Antenna subarray formation (ASF) has been recently proposed as an alternative method to Antenna Selection that reduces hardware complexity while offering increased data rates. With this method each RF chain is not allocated to a single element but instead to the combined and weighted output of a subarray of elements. In this paper, we remove the restriction that each antenna element must participate in only one subarray and study the capacity performance when a given number of phase shifters and variable gain amplifiers are available at the receiver. To further reduce the hardware complexity, we introduce a version that discards the variable gain amplifiers. A fast and efficient algorithm for ASF is used, which offers remarkably high data rates while maintaining low hardware and computational complexity.