On the LLR Metrics for DPSK Modulations Over Two-Symbol Observation Intervals for the Flat Rician Fading Channel

Adaptive Coherent/Non-Coherent Single/Multiple-Antenna Aided Channel Coded Ground-to-Air Aeronautical Communication

“…Our simulation results demonstrate that the accuracy of CSI estimation degrades upon increasing the aircraft velocity. As a result, the MSDSD and DFDD solutions are capable of outperforming their coherent counterparts at [16] CDD Soft × × √ × Divsalar et al [17] MSDD Hard × √ √ × Cui et al [18] MSDSD Hard √ √ × × Schober et al [13] DFDD Hard √ √ √ × Lampe et al [15] DFDD Soft √ √ √ × Our solutions MSDSD/DFDD Hard/Soft √ √ √ √ [19], [20] Rm = high Doppler frequencies. (4) In order to fully exploit the advantages of the proposed techniques, we propose for the aeronautical communication networks to be able to adaptively (I) switch between coherent and non-coherent schemes at low and high f d , respectively, (II) switch between singleand multiple-TA single-RF schemes at low and high channel coding rate R c , respectively, and (III) switch between high-diversity and high-throughput MIMO schemes at low and high modulation throughput R m , respectively.…”

“…However, the metric ∆ D u in (16) is not directly decomposed from d D in (14). For this reason, the previous ∆ D u−1 is cancelled out from (16). As a result, the MSDD metric of (14) is unambiguously recovered by the PED of (15), when the SD index reaches u = N w .…”

“…Based on (15)- (16), the MSDSD algorithm of [10] using the Schnorr-Euchner search strategy may be invoked. An example of MSDSD (N w = 3) aided DQPSK is portrayed in Fig.…”

“…3 starts from index u = 1, where the PED d 1 is initialized according to (15). The SD increases its index to u = 2 and evaluates the four candidate PED increments ∆ u based on (16). The lowest value of ∆ u = 0.65 is chosen, which updates the PED of d 2 = 2.47.…”

“…The MSDSD for DSTM may use the same VLM algorithm as the MSDSD for DPSK, where ∆ S u in (16) and (18) may be modified as:…”