Performance analysis of combining scheduling and space-time block coding under channel estimation error

This study analyses performance-based implications of combining user scheduling and space–time block coding (STBC) (i.e. joint diversity) under channel estimation error. The exact closed-form expression of joint diversity for the achievable rate is derived. Moreover, the approximate closed-form expression of joint diversity for the outage achievable rate is derived through Gaussian approximation. The exact closed-form expression of joint diversity for the outage probability is finally derived, including the quantification of the order of diversity and the signal-to-noise ratio (SNR) gain. Using analytical results, it is demonstrated that both the achievable rate and the outage achievable rate of joint diversity improves as the number of user terminals increases through multiuser diversity. The approximate results of the analysis and simulation of the outage achievable rate for joint diversity are well matched as the number of users increases. The outage probability enhances with the number of user terminals through diversity order improvement, whereas the SNR gain is identical to that in conventional non-scheduling STBC.