In order to effectively suppress the strong turbulence effect caused by the wake of helicopter during landing, diversity reception technology was used for suppression. According to the characteristics of wireless ultraviolet slant communication and approximate-line-of-sight (ALOS) communication, the probability density function of edge distribution of the received signal strength was given. The correction model of UV ALOS communication system based on gamma-gamma distribution was established. The diversity reception technology was introduced into the model. The influence of turbulence effect on the edge probability density distribution of optical signal intensity was analyzed theoretically. Bit error performances of maximal ratio combining (MRC), equal gain combining (EGC) and selective combining (SC) were analyzed. The results show that, the stronger the turbulence intensity is, the worse the bit error rate performance of UV ALOS system is. With two diversities, the signal-to-noise rates of MRC, EGC and SC have increased 22dB, 18dB and 16dB respectively. The diversity reception technology can effectively suppress the strong turbulence effect in helicopter assisted landing and improve the stability and anti-fading performance of communication system.