A Novel ZF and MMSE Receiver for Modified Walsh-Hadamard Code Division Multiplexing in Helicopter Satellite Communications

In helicopter satellite communications, overcoming periodic signal blockage caused by rotor blades is an important issue. Modified Walsh-Hadamard code division multiplexing (MWHCDM) is a promising solution. However, it is adversely affected by the inter-code interference (ICI) due to the periodic blockage. This paper proposes an ICI reduction scheme for MWHCDM. The proposed one utilizes the structure of the MWHCDM signal for reducing the ICI with zero-forcing (ZF) and minimum mean square error (MMSE) detection. The results of computer simulation demonstrated that the proposed one achieves both excellent bit error rate performance and superior spectral efficiency in the periodic blockage channel.