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In this paper, we evaluate a multilevel coding (MLC) scheme with multi-stage decoding (MSD) designed for satellite broadcasting communications, where services with different quality of service (QoS) are desirable. A simple Land-Mobile-Satellite (LMS) channel model is presented, based on channel states and their transitions. The instantaneous channel capacity for suburban and forest scenarios is calculated...
The faster-than-Nyquist (FTN) signaling has been of interest in the research literature due to recent advances in pre-coding and equalization techniques allowing practical removal of the intersymbol interference (ISI). Since the structure of ISI is deterministic in the FTN signaling, a data pre-coding at the transmitter to combat ISI is of practical importance. It is shown, however, that such pre-coding...
In this paper we propose a novel connection admission control scheme named Rate Transition Area assisted Guaranteed Handover Scheme (GHS-RTA), which utilizes the geographical information, rate transition areas and overlap areas to intelligently decide when to block a new call. This scheme helps avoid possible inter-cell and intra-cell handover failures for HAP communications systems with adaptive...
Smart antennas have received increasing interest due to its capability for improving the performance of wireless radio systems. In this work we studied the throughput maximization in a CDMA 1xEV-DO cellular system when a smart antenna array is implemented. We focus in the downlink of the CDMA cellular system and consider a packet data direct-sequence code division multiple access (DS-CDMA). We show...
We consider multicasting the same data from one base station (BS) to several user equipments (UE) over a radio interface. Transmission is slotted into transmit resource units (RU). The qualities of the transmission channels from the BS to the UEs differ between RUs and between UEs. The transmit rate can be chosen by the BS independently in each RU based on the per UE channel qualities, which are assumed...
The effort dedicated to the ultimate goal of designing an architectural framework for tactical mobile ad hoc networks (MANETs) has long been hindered by the excessive control overhead of routing protocols to maintain a full view of the network topology. This paper explores the viability of adopting network coding as a means of improving reliable data delivery while lowering control overhead in large...
In this contribution, we propose a Distributed Concatenated Irregular Convolutional Coded Unity Rate Coded and Space Time Trellis Coded (DC-IrCC-URC-STTC) scheme for cooperative communications employing multiple single-antenna relays. Each coding arrangement is designed for efficient decoding convergence by employing non-binary Extrinsic Information Transfer (EXIT) charts. The source node transmits...
In this paper, we propose a new multi-user receiver processing for PUCCH LTE that counteracts the ICI in a non-cooperative multi-cell architecture. Using the fact that the received signal in PUCCH signaling follows a constrained tensor model, a multi-user receiver based on an iterative joint channel/code estimation and symbol detection is proposed. The interest in such a challenging setting relies...
The steady-state throughput of general network coding node is investigated, when data is transmitted in packets based on the stop-and-wait automatic repeat request (SW-ARQ) error-control scheme. The general network coding node has H number of incoming links that provide packets for forming the coded packets transmitted by one outgoing link. Each of the incoming and outgoing links is assumed to have...
There are few analytical formulas that can be used for calculating the block error rate (BLER) in block fading channels. Thus, an estimate of the BLER is often obtained using numerical methods. One such method is the threshold method which assigns 0 or 1 to the instantaneous BLER given the signal to noise ratio (SNR) level. It has been shown that utilizing such a method results in an accurate approximation...
Systematic Luby Transform (SLT) codes constitute rateless codes, which are capable of adaptively adjusting their code rate depending on the channel quality without explicit channel state information (CSI) at the transmitters. SLTs are also suitable for space-time collaboration aided relay networks. In this paper, an iterative decoding aided SLT scheme is combined with 16-QAM transmission in a wireless...
In this paper, a joint channel-network coding is proposed for the multiple access half duplex relay channel. To improve performance, the classical constraints of orthogonality between links are partially relaxed, i.e., in the first transmission phase the two sources are allowed to transmit simultaneously, while in the second phase, the relay transmits alone and the sources are silent. In order to...
We analyse mobile propagation channels which occur in the context of car-to-car communications in the 24~GHz ISM band. From the information gathered, we design robust frame designs for combined radar and communication systems using high-bandwidth OFDM signals. Two solutions are proposed: the combination of a spread spectrum technique and a standard convolutional encoder, as well as a low rate Reed-Muller...
We consider the problem of designing cooperative driver assistance and collision warning systems in vehicular networks. In this problem each car has a small size state information message that should be received by its neighborhood within a short lifetime of L timeslots. Because of the safety nature of the application, communication reliability (success probability) and delay are of critical importance...
The compress-and-forward relay scheme developed by (Cover and El Gamal, 1979) is modified by realizing that it is not necessary for the destination to decode the compressed observation of the relay; and even if the compressed observation is to be decoded, it can be more easily done by joint decoding with the original message, rather than in a successive way. This modification introduces flexibility...
We derive in this paper the bit error probability and cutoff rate of an Amplify-and-Forward (AF) relay system operating in Rayleigh fast fading. In our model, we consider the relay thermal noise to be non-negligible and derive a closed form expression to approximate the bit error probability. Our approximated closed form expression matches well with simulation result. Using Chernoff bound, we upper...
In this paper, we investigate the optimal power and time allocation for a wireless relay network, called BCFR (Broadcasting Channel with Fixed Relay), where the relay node is limited by the half-duplex operation. Introducing a relay in two-node broadcasting channel for a node which has a link of bad quality or requires higher transmission rate enlarges the rate region with well-designed power and...
Tailbiting convolutional codes will be used for several applications in new cellular mobile radio systems. This encoding method does not reset the encoder memory at the end of each data block, avoiding the overhead of the zero tail and improving the efficiency. Nevertheless, the absence of a known tail highly increases the complexity of the decoding process. Recently, the use of the A* algorithm has...
A generalised vector precoding (VP) design based on the minimum bit error rate (MBER) criterion is proposed for multiuser transmission in the downlink of a multiuser system where the base station (BS) equipped with multiple transmit antennas communicates with single-receive-antenna mobile station (MS) receivers each having a modulo detection device. Our transmit preprocessing scheme generates the...
We propose a data precoded relay-assisted scheme, for a system cooperating with 2 relays. We assume that all the terminals are equipped with a single antenna. The use of relays is of significant interest to allow radio access in situations where a direct path is not available. However because of the half duplex constraint at the relays, transmission of a data rate equivalent to that of a modulation...
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