Several polling algorithms have been proposed to overcome the slot wastage problem due to the exchange of POLL or NULL packets in the case of no data to transmit. However, most of these algorithms suffer from achieving the fairness among all slaves. This paper proposes two scheduling algorithms, Uplink Downlink Limited Round Robin (LRR) with fixed cycle time and Uplink Downlink LRR with adaptiv...

This paper focuses on signal space interference alignment for the uplink and downlink transmissions in a cellular relay network with multiple cells where a single base station serves multiple mobile stations in each cell and several amplifyand-forward relays are deployed. We show that the interference alignment problems in the uplink and downlink transmissions are a pair of formally dual proble...

The shared time division multiplexing (shared-TDD) scheme has been proposed to accommodate asymmetric communications between uplink and downlink. The accommodation of connection-less services in Shared-TDD systems causes a difficulty of TDD boundary control. This paper proposes a TDD boundary control (resource assignment) scheme, which can optimize a position of the TDD boundary based on the ra...

The idea of adaptive usage of uplink frequency resources for other purposes, such as downlink data transmission, has attracted researchers for many years. As an extension of the conference paper on the same subject, this article discusses the concept of applying a multichannel simultaneous uplink and downlink transmission scheme for flexible duplexing, where the middle part of the so-called upl...

This paper considers a cellular system with a fullduplex base station and half-duplex users. The base station can activate one user in uplink or downlink (half-duplex mode), or two different users one in each direction simultaneously (full-duplex mode). Simultaneous transmissions in uplink and downlink causes self-interference at the base station and uplinkto-downlink interference at the downli...

Ambient radio frequency (RF) energy harvesting has emerged as a promising solution for powering small devices and sensors in massive Internet of Things (IoT) ecosystem due to its ubiquity and cost efficiency. In this paper, we study joint uplink and downlink coverage of cellular-based ambient RF energy harvesting IoT where the cellular network is assumed to be the only source of RF energy. We c...

The mobile WiMAX systems based on IEEE 802.16e-2005 provide high data rate for mobile wireless networks. However, the link quality is frequently unstable owing to mobility and air interference and therefore impacts the latency requirement of real-time applications. In the WiMAX standard, the modulation/ coding scheme and the boundary of uplink/downlink sub-frames could be adjusted subject to ch...

The total whole-body exposure dose in indoor wireless networks is minimized. For the first time, indoor wireless networks are designed and simulated for a minimal exposure dose, where both uplink and downlink are considered. The impact of the minimization is numerically assessed for four scenarios: two WiFi configurations with different throughputs, a Universal Mobile Telecommunications System ...

Location-aware communication systems are expected to play a pivotal part in the next generation of mobile communication networks. Therefore, there is a need to understand the localization limits in these networks, particularly, using millimeter-wave technology (mmWave). Towards that, we address the uplink and downlink localization limits in terms of 3D position and orientation error bounds for ...

Our traditional notion of a cell is changing dramatically given the increasing degree of heterogeneity in 4G and emerging 5G systems. Rather than belonging to a specific cell, a device would choose the most suitable connection from the plethora of connections available. In such a setting, given the transmission powers differ significantly between downlink (DL) and uplink (UL), a wireless device...