From: A comparison between APSK and QAM in wireless tactical scenarios for land mobile systems
Modulation
ρ= 0.1
ρ= 0.3
ρ = 0.5
16-QAM
7.2 dB
6.3 dB
5.7 dB
4+12-APSK
4.8 dB
4.2 dB