This paper addresses a more practical relay network consisting of a mobile source, multiple distributed mobile amplify-and-forward (AF) relays, and a mobile destination node. It considers an appropriate channel model between nodes, which is a cascaded Rayleigh fading channel. The objective of this paper is to determine an optimum AF relay vector (or matrix) using the minimum mean square error (MMSE) criteria for these distributed AF relay networks. The effects of jamming and imperfect channel state information (ICSI) on network performance are included in the analysis. Additionally, by substituting the derived amplifying relay vectors into the MMSE cost functions, it can be
predicted which case will yield a better BER performance.