A new capture effect, ‘neighborhood capture’, is described, which arises when Ethernet-type protocols are employed in multiple-cell wireless local area networks (WLANs) that re-use RF channels. Given the small number of channels available, co-channel cells cannot all transmit simultaneously without causing interference on one another. A carrier-sense contention-based MAC protocol can allocate c...

We propose and analyze a specific set of access rules, or “spectrum etiquette,” for the 59-64 GHz unlicensed band to allow systems from different manufacturers with different physical and medium-access control protocols to co-exist, sharing the large available bandwidth without interference. The proposed etiquette is unique in that heterogeneous systems are able to co-exist with one another, wi...

We propose and analyze a specific set of access rules, or “spectrum etiquette,” for the 59–64 GHz unlicensed band to allow systems from different manufacturers with different physical and medium-access control protocols to co-exist, sharing the large available bandwidth without interference. The proposed etiquette is unique in that heterogeneous systems are able to co-exist with one another, wi...

This report presents results of computer simulations and laboratory tests conducted at the CRC to investigate various channel coding techniques proposed for the terrestrial broadcasting of digital advanced television (ATV). The system performance of these techniques is evaluated for various impairments, such as Gaussian noise and co-channel NTSC and ATV interference. The performance of NTSC wit...

We present a novel frequency partitioning technique of fractional frequency reuse (FFR) that reduces the effect of co-channel interference and increases the capacity of OFDM systems. The usable sub-channel sets are classified into the common sub-channel sets for all cells and the dedicated sub-channel sets for specific cell types in FFR. The proposed fractional frequency reuse with ordering sch...

Orthogonal frequency division multiplexing (OFDM) is a promising technique for high-data-rate wireless communications because it can combat inter-symbol interference (ISI) caused by the dispersive fading of wireless channels. The proposed research focuses on techniques that improve the performance of OFDM based wireless communications and its commercial and military applications. In particular,...

Femtocells have been considered as a promising technology to provide better indoor coverage and spatial reuse gains. However, the co-channel deployment of macrocells and femtocells is still facing challenges arising from potentially severe inter-cell interference. In this article, we investigate the uplink resource allocation problem of femtocells in co-channel deployment with macrocells. We fi...

Direct sequence (DS) code division multiple access (CDMA) is a promising technology for wireless communication with multiple simultaneous transmissions. The capacity of DS-CDMA is interference-limited and can therefore be increased by techniques that suppress interference. In this paper, an interference cancellation method is given. We propose a novel parallel interference cancellation detector...

This article deals with the frequency assignment problem (FAP) in slow frequency hopping (GSM) networks, a generalization of the classical FAP. Due to symmetry in the solutions, a natural integer linear programming formulation does not yield a good solution procedure. Instead, we decompose the co-channel and adjacent channel interference minimization and develop a two-stage algorithm. The co-ch...