In this paper, full-duplex radios are used to continuously update the channel state information at the transmitter, which is required to compute the downlink precoding matrix in MIMO broadcast channels. The full-duplex operation allows leveraging channel reciprocity for open-loop uplink training to estimate the downlink channels. However, the uplink transmission of training creates interference...

|This paper proposes a transmission power control scheme for downlinks in CDMA/shared{TDD cellular packet systems that experience inter-cell interference between uplinks and downlinks. The proposed scheme increases the downlink transmission power for re-transmission packets and thus improves the signalto-interference ratio for the packets. Simulation results show that the proposed scheme improv...

In this paper, the downlink soft handover gain is analysed in UMTS networks under three different power control situations: without power control, with perfect power control and with imperfect power control. The results show that although power control in the downlink direction is not as crucial as it in the uplink direction, it does have a significant influence on the downlink soft handover ga...

In this study, the authors consider the benefits of mobile terminals (MTs) with different access points (APs) for uplink and downlink transmission to conserve MTs’ energy. In traditional cellular networks, an MT is typically associated with a single AP. However, as wireless networks evolve, heterogeneous and/or overlay deployment scenario become viable and an MT can be associated with different...

Recently, multimedia services are increasing with the widespread use of various wireless applications such as web browsers, real-time video, and interactive games, which results in traffic asymmetry between the uplink and downlink. Hence, time division duplex (TDD) systems which provide advantages in efficient bandwidth utilization under asymmetric traffic environments have become one of the mo...

Full-duplex (FD) transmission in a point-to-point (P2P) link, wherein bidirectional traffic flows simultaneously share the same spectrum, has the capability of doubling the link throughput by completely removing self-interferences. However, the throughput gain of FD transmission in an interference-limited network is not as clear as a P2P link due to the interferences induced by complex FD and h...

Downlink beamforming is a promising technique €or DS-CDMA systems with multimedia services to eflectively reduce strong interferences induced by high data rate users. In this paper, we first proposed a new downlink beamforming algorithm which converts downlink beamforming problem to a virtual uplink one and takes into account of the data rate information of all users. Since the main complexity ...

This paper investigates downlink channel estimation in frequency-division duplex (FDD)-based massive multiple-input multiple-output (MIMO) systems. To reduce the overhead of downlink channel estimation and uplink feedback in FDD systems, cascaded precoding has been used in massive MIMO such that only a low-dimensional effective channel needs to be estimated and fed back. On the other hand, trad...

Uplink scheduling in wireless systems is gaining importance due to arising uplink intensive data services (ftp, image uploads etc.), which could be hampered by the currently in-built asymmetry in favor of the downlink. In this work, we propose and study algorithms for efficient uplink packet-data scheduling in a CDMA cell. The algorithms attempt to maximize system throughput under transmit powe...