Harmonic Mean and End-to-End Performance of Transmission Systems With Relays

Switched diversity strategies for dual-hop relaying systems

“…The end-to-end SNR of AF dual-hop relaying systems, denoted by γ c , has a well-known form [10], [9], which generally can be expressed as γ c = γ1γ2 γ1+γ2+b , where γ 1 and γ 2 are the combined SNRs on the first and second hops respectively, and b is a constant. The case when b = 0 represents the channel-assisted relay configuration, whereas b = 1 gives the channel noiseassisted relay configuration.…”

“…A simple relaying system consists of a single relay station, wherein the direct path between the transmitter and the receiver is replaced by the relaying path to overcome the effects of limited transmit power, deep large-scale fading, and invisible direct transmission. Extensive research has been devoted to the performance analysis of dual-hop relaying using non-regenerative protocols, such as the well-known amplifyand forward (AF), due to their simplicity [6]- [10]. It has been also shown that the use of diversity combining schemes, such as MRC and SC, in dual-hop AF relaying can reduce the effect of multipath fading and improve the system capacity [11], [12].…”

Wireless Transmissions with Combined Gain Relays over Fading Channels

“…Looking through the recent up-to-date open technical literature, the performance of dual-hop wireless communication systems are studied in [I], [4], [5], [6], [7]. Hasna and Alouini have presented a useful and semi-analytical framework for the evaluation of the end-to-end outage probability of multihop wireless systems with non-regenerative channel state information (CS1)-assisted relays over Nakagami-m fading channels [I].…”

“…Hasna and Alouini have presented a useful and semi-analytical framework for the evaluation of the end-to-end outage probability of multihop wireless systems with non-regenerative channel state information (CS1)-assisted relays over Nakagami-m fading channels [I]. Moreover, the same authors have studied the outage and the error performance of dual-hop systems with regenerative and non-regenerative CSI-assisted relays over Rayleigh [4] and Nakagami-m [5] fading channels. The analysis in [I], [4], and [5] is based on an upper bound for the end-to-end signal-to-noise ratio (SNR) which leads to lower bounds for the system's outage and average error probability.…”

“…Moreover, the same authors have studied the outage and the error performance of dual-hop systems with regenerative and non-regenerative CSI-assisted relays over Rayleigh [4] and Nakagami-m [5] fading channels. The analysis in [I], [4], and [5] is based on an upper bound for the end-to-end signal-to-noise ratio (SNR) which leads to lower bounds for the system's outage and average error probability. This bound corresponds to an ideal relay capable of inverting the channel in the previous hop (regardless of the fading state of that hop) without limiting the output power.…”