Analysis of Coverage Region for MIMO Relay Network with Multiple   Cooperative DF-Relays
  We study and analyze coverage region in MIMO communication systems for a multiple-relay network with decode-and-forward (DF) strategy at the relays. Assuming that there is a line-of-sight (LOS) propagation environment for source-relay channels and channel state information is available at receivers (CSIR), we consider the objective of maximizing coverage region for a given transmission rate and show numerically the significant effect of propagation environment on capacity bounds, optimal relay location and coverage region. Also, we study the situation in which two adjacent relays cooperate in transmission signals to the destination and show analytically that the coverage region is extended compared to noncooperative scenario. 
Behrooz Razeghi, Alireza Alizadeh, Sima Naseri, Ghosheh Abed Hodtani,   Seyed Alireza Seyedin
cs.IT math.IT