Signal‐to‐noise‐ratio maximisation for linear multi‐antenna relay communications

Frequency Diverse Array Antenna: New Opportunities

“…Equation (20) reveals that the angle dependence is found in the phase term only, whereas the amplitude depends on the time, the range, and the frequency increment only and no longer on the angle. It can be observed in Figure 9 that the array factor exhibits a constant peak gain with the angle at a particular range.…”

“…Although techniques exist to assist in mitigating range-dependent interferences, such as the space-time adaptive processing technique [12][13][14][15][16], they have a high computational cost. On the other hand, the desire for new and more advanced array antennas is driven by the requirements of many emerging applications ranging from multitask radar [17] to radio astronomy [18] and relay communication systems [19,20].…”

Optimal multi‐input–multi‐output relay transform matrix with a bounded condition number

“…whereR X = E s {XX H } for X = GE, Hs, E, s. Several reasons that justify the usefulness of maximising the SNR are presented in [11]. In particular, it is shown that maximising the individual SNRs is a better criterion than maximising the individual link capacities in a multi-user environment.…”

“…That is, the relay matrices that maximise (2), provide a higher data rate than maximising individual link capacities (see Fig. 7 in [11]). [11].…”

“…Maximisation of the SNR of a communication system is the criterion in [11], and assuming restricted relay transmit power, the optimal RTM is derived. The optimal RTM allocates all the relay transmit power to the dominant eigenvectors of the source-relay (SR) and the relaydestination (RD) channels matrices [11].…”