Analysis of MFSK/FH System Based on Adaptive Array Antenna with Beamforming Technique

Anti-jamming/interference is the most important issue in the wireless communication. In this paper, based on the traditional M-array FSK modulation (MFSK/FH) system, an array antenna using the adaptive beamforming (BF) technique is adopted in the traditional MFSK/FH receiver (i.e., MFSK/FH-BF system), which improves the anti-jamming performance. Firstly, a modified FH-BF receiver using a uniform circle antenna (UCA), which is suitable for FH waveform, is proposed to reduce the effect of hopped frequency on the directions of the beam pattern. Then, the numerical relations among the FH parameters (e.g., the number of frequency slots), BF parameter (e.g., the number of snapshots), and system performance (bit-error rate and output signal-to-interference-plus-noise ratio) are systematically analyzed by theoretical analysis. Finally, the performance of the MFSK/FH-BF system is verified by simulation analysis. The theoretical and simulation results show that the direction of the beam pattern of the proposed BF-MFSK/FH system converges fast. On top of that, the proposed system is shown to be robust and capable of outperforming traditional systems with single frequency technique and single spatial technique (e.g., MFSK/FH system and MFSK-BF system) under complex jamming environments. It can be deployed in satellite systems, battlefield communication, and 5G cellular networks.