Distributed Interleave-Division Multiplexing Space-Time Codes for coded relay networks

Reliability-aware iterative detection scheme (RAID) for distributed IDM space-time codes in relay systems

“…The algorithm requires the set of all CRC check results CRC m,n , the set of all error probabilities q m,n , the set of all channel impulse http://asp.eurasipjournals.com/content/2013/1/70 responses from the relays to the destination g n , the sets of all relay specific and user specific interleavers r,n and { n } and the noise variance σ 2 n . After the grouping, as described in Section 4.2.1 (lines [3][4][5][6][7][8][9][10][11][12][13][14], the iterative detection process is performed (lines 15-35). Besides some interleaving and de-interleaving operations, it mainly consists of the softRAKE detection (line 18), the combining of the information from the correct relays (line 22) and the APP-decoding (lines 27-28).…”

“…The reliability information of all relays was then used for a weighted combining of the relay messages. As a result, a significant performance improvement was achieved compared to the common detection scheme for dIDM-STC from [12]. However, it could also be seen that the actual usage of the available information at the destination was not yet optimal as the results indicated a performance gap compared to adaptive relaying schemes in which only correct relays forward to the destination.…”

“…Consequently, the IDM-STC has been applied to relay systems in a distributed fashion using uncoded transmission and the Decode-and-Forward (DF) relaying protocol [11]. In [12], the principles of distributed IDM-STCs (dIDM-STCs) have been extended to coded systems and further relay protocols like Amplify-andForward (AF) and Decode-Estimate-and-Forward (DEF). It has been shown, that the dIDM-STC is in fact a good choice for relaying systems due to its flexibility regarding code rate and number of transmitting nodes and due to its robustness against asynchronisms.…”

An Improved Detection Scheme for Distributed IDM-STCs in Relay-Systems

“…Specifically, the relay signals have been weighted according to the reliability of the corresponding relays, before they have been combined. The resulting DFq-INST scheme has shown a significant performance improvement compared to the common detection scheme from [9]. However, the achieved performance was still poor compared to adaptive relay schemes in which only correct relays forward to the destination, while all erroneous relays stay silent [4].…”

“…This InterleaveDivision-Multiplexing Space-Time Code (IDM-STC) does not require any synchronisation among the transmitting nodes, making it a promising candidate also for relay systems. Hence, the IDM-STC has first been applied to uncoded Decodeand-Forward (DF) relay systems in a distributed fashion in [8] and has later on been extended for coded systems and additional relay protocols in [9]. It has been shown, that…”