Square Complex Orthogonal Designs with no Zero Entry for any $2^m$ Antennas

TL;DR

This paper introduces a general construction method for square complex orthogonal designs with no zero entries for any power of 2 antennas, improving peak power performance over existing designs.

Contribution

The paper presents a novel, general construction technique for zero-entry-free SCODs applicable to any power of 2 antennas, filling a gap in existing methods.

Findings

Outperforms existing codes under peak power constraints

Maintains comparable performance under average power constraints

Applicable to any number of antennas that is a power of 2

Abstract

Space-time block codes from square complex orthogonal designs (SCOD) have been extensively studied and most of the existing SCODs contain large number of zeros. The zeros in the designs result in high peak-to-average power ratio and also impose a severe constraint on hardware implementation of the code while turning off some of the transmitting antennas whenever a zero is transmitted. Recently, SCODs with no zero entry have been constructed for $2^a$ transmit antennas whenever $a+1$ is a power of 2. Though there exists codes for 4 and 16 transmit antennas with no zero entry, there is no general method of construction which gives codes for any number of transmit antennas. In this paper, we construct SCODs for any power of 2 number of transmit antennas having all its entries non-zero. Simulation results show that the codes constructed in this paper outperform the existing codes for the same number of antennas under peak power constraint while performing the same under average power constraint.