Low-complexity Noncoherent Maximum Likelihood Sequence Detection Scheme for CPM in Aeronautical Telemetry

TL;DR

This paper introduces a low-complexity noncoherent MLSD scheme for CPM in aeronautical telemetry, improving efficiency and robustness without sacrificing detection performance, suitable for high spectral and power efficiency applications.

Contribution

The paper proposes a novel noncoherent MLSD method with a modified Viterbi algorithm that reduces complexity and eliminates the need for carrier phase recovery in CPM systems.

Findings

Lower computational complexity compared to traditional MLSD

No need for accurate carrier phase recovery

Achieves similar detection performance as traditional MLSD

Abstract

Due to high spectral efficiency and power efficiency, the continuous phase modulation (CPM) technique with constant envelope is widely used in aeronautical telemetry in strategic weapons and rockets, which are essential for national defence and aeronautic application. How to improve the bit error rate (BER) performance of CPM and keep a reasonable complexity is key for the entire telemetry system and has been the focus of research and engineering design. In this paper, a low-complexity noncoherent maximum likelihood sequence detection (MLSD) scheme for CPM is proposed. In the proposed method, the criterion of noncoherent MLSD for CPM is derived when the carrier phase is unknown, and then a novel Viterbi algorithm (VA) with modified state vector is designed to simplify the implementation of noncoherent MLSD. Both analysis and experimental results show that the proposed approach has lower computational complexity and does not need accurate carrier phase recovery, which overcomes the shortage of traditional MLSD method. What's more, compared to the traditional MLSD method, the proposed method also achieves almost the same detection performance.