Multiuser detection for time synchronous ARGOS signals

In this paper, we investigate the application of multiuser detection techniques to a Low Polar Orbit (LPO) mobile satellite used in the ARGOS system. These techniques are used to mitigate the multiple access interference in the uplink transmission of the system. Unlike CDMA, due to the Doppler Effect, each signal has a different received carrier frequency and a different propagation delay. Multiuser detection techniques are proposed for asynchronous transmission in ARGOS system: the maximum likelihood detector, the conventional detector, and the sequential interference cancellation detector, as solutions to tackle the interference effects. Bit Error Rate performance graphs are shown for these techniques.

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“…in the same way as in the synchronous case [3], the complexity grows exponentially with the length of the vector ' b i.e. O(2 KM ).…”

Section: Maximum Likelihood Detectormentioning

confidence: 93%

“…For the ARGOS system, several MUD techniques have been already designed for synchronous scenarios i.e. when all the signals are assumed to be received at the same time [3]. This paper investigates optimum and sub optimum MUD techniques for the reception of asynchronous users.…”

Section: Introductionmentioning

confidence: 99%

Multiuser detection for asynchronous ARGOS signals

Fares¹,

Boucheret²,

Escrig³

et al. 2010

2010 7th International Symposium on Communication Systems, Networks &Amp; Digital Signal Processing (CSNDSP 2010)

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“…We note that the symbol b l ( u ) of user l is correlated with the symbols b k ( u ) of the other ( K − 1) users, that is, for k ∈ [1, K ] and k ≠ l , with the symbols b k ( u + 1) of the preceding users, that is, for k ∈ [1, l − 1] and with the symbols b k ( u − 1) of the following users, that is, for k ∈ [ l + 1, K ] . Thus, is written as

\begin{matrix} leftalign-star \\ rightalign-odd y_{l} MathClass-open(u MathClass-close) & align-even = \sum_{k = 1}^{K} A_{k} cos MathClass-open(m MathClass-close) ρ' MathClass-open(u MathClass-close) + j \sum_{k = 1}^{K} A_{k} sin MathClass-open(m MathClass-close) b_{k} MathClass-open(u MathClass-close) ρ_{l, k} MathClass-open(u, u MathClass-close) & rightalign-label & align-label \\ rightalign-odd & align-even + j \sum_{k = 1}^{l - 1} A_{k} sin MathClass-open(m MathClass-close) b_{k} MathClass-open(u + 1 MathClass-close) ρ_{l, k} MathClass-open(u, u + 1 MathClass-close) + j \sum_{k = l + 1}^{K} A_{k} sin MathClass-open(m MathClass-close) b_{k} MathClass-open(u - 1 MathClass-close) ρ_{l, k} MathClass-open(u, u - 1 MathClass-close) & rightalign-label & align-label \\ rightalign-odd & align-even \end{matrix}

…”

Section: Mud Receivers For Asynchronous Argos Usersmentioning

confidence: 99%

“…Recall that h ( t ) is the unit energy signature waveform with a value of

1 MathClass-bin∕ \sqrt{T}

over the interval [0, T ∕ 2] and a value of

MathClass-bin- 1 MathClass-bin∕ \sqrt{T}

over the interval [ T ∕ 2, T ]. In a similar way as in , the coefficients ρ ′ ( u ) are given by

ρ MathClass-rel' (u) MathClass-rel= ζ_{l MathClass-punc, k} (τ_{l} MathClass-punc, τ_{l} MathClass-bin+ T MathClass-bin∕ 2 MathClass-punc, u) MathClass-bin- ζ_{l MathClass-punc, k} (τ_{l} MathClass-bin+ T MathClass-bin∕ 2 MathClass-punc, τ_{l} MathClass-bin+ T MathClass-punc, u)

The computation of the coefficients ρ l , k ( u , n ) have been addressed in for non‐return‐to‐zero signals. We present here the main results for a bi‐phase signal.…”

Section: Mud Receivers For Asynchronous Argos Usersmentioning

confidence: 99%

See 1 more Smart Citation

Multi‐user detection for the ARGOS satellite system

Escrig

Fares

Boucheret

et al. 2014

Satell Commun Network

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OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible. This is an author-deposited version published in : http://oatao.univ-toulouse.fr/ Eprints ID : 12920 SUMMARYIn this paper, we evaluate several Multi-User Detection (MUD) architectures for the reception of asynchronous beacon signals in the ARGOS satellite system. The case of synchronous signals is studied first. Though impractical, this case provides useful guidance on the second part of the study, i.e., the design of MUD receivers for asynchronous users. This paper focuses more particularly on Successive Interference Cancellation (SIC) receivers since they have been shown to achieve a good performance complexity tradeoff. Several E b /N 0 degradation curves are obtained as a function of channel parameters. With these curves, a performance analysis is presented in order to determine in which conditions it is possible to successfully decode none, one, or more beacon signals. We show that SIC receivers can improve the percentage of served beacons from 50% to more than 67% for a population of 37,600 beacons.

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