High-rate, single-symbol decodable distributed STBCs for partially-coherent cooperative networks

Abstract

Abstract-Space-time block codes (STBCs) that are single-symbol decodable (SSD) in a co-located multiple antenna setting need not be SSD in a distributed cooperative communication setting. A relay network with N relays and a single source-destination pair is called a partially-coherent relay channel (PCRC) if the destination has perfect channel state information (CSI) of all the channels and the relays have only the phase information of the source-to-relay channels. In our earlier work, we had derived a set of necessary and sufficient conditions for a distributed STBC (DSTBC) to be SSD for a PCRC. Using these conditions, in this paper we show that the possibility of channel phase compensation operation at the relay nodes using partial CSI at the relays increases the possible rate of SSD DSTBCs from , which is independent of N . We also show that when a DSTBC is SSD for a PCRC, then arbitrary coordinate interleaving of the in-phase and quadrature-phase components of the variables does not disturb its SSD property. Using this property we are able to construct codes that are SSD and have higher rate than 2 N but giving full diversity only for signal constellations satisfying certain conditions.

Cascaded orthogonal space–time block codes for wireless multi-hop relay networks

“…Previous constructions of maximum diversity gain achieving DSTBCs with low decoding complexity (single symbol decodable) [14][15][16][17][18][19][20][21] are limited to a two-hop network with single antenna nodes. COSTBCs, in comparison, achieve the maximum diversity gain with linear decoding complexity (similar to [14][15][16][17][18][19][20][21]) in a multi-hop network with multiple antenna equipped nodes, even though they do not have the single symbol decodable property.…”

“…COSTBCs, in comparison, achieve the maximum diversity gain with linear decoding complexity (similar to [14][15][16][17][18][19][20][21]) in a multi-hop network with multiple antenna equipped nodes, even though they do not have the single symbol decodable property. For the multi-hop network, the focus of [23,24] is on the construction of DSTBCs that can achieve the optimal diversity multiplexing tradeoff [29].…”

“…In prior work, maximum diversity gain achieving DSTBC constructions have been proposed for the twohop network [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21], and for the multi-hop network [22][23][24]. Even though these DSTBC constructions achieve the maximum diversity gain, the decoding complexity of most of them, except [14][15][16][17][18][19][20][21], is very high, thereby limiting their use in practical deployment.…”

“…Even though these DSTBC constructions achieve the maximum diversity gain, the decoding complexity of most of them, except [14][15][16][17][18][19][20][21], is very high, thereby limiting their use in practical deployment. Construction of DSTBCs with low decoding complexity is practically important as highlighted by the fact that the Alamouti code is the most practically used code not only because it achieves the maximum diversity gain, but also because it requires minimum decoding complexity.…”

“…Construction of DSTBCs with low decoding complexity is practically important as highlighted by the fact that the Alamouti code is the most practically used code not only because it achieves the maximum diversity gain, but also because it requires minimum decoding complexity. Moreover, the DSTBC constructions with low decoding complexity [14][15][16][17][18][19][20][21] are limited to two-hop network with single antenna equipped source, destination, and the relay nodes.…”