© 2015 Rugui Yao et al. 11 http://dx.doi.org/10.4218/etrij.15.0114.0758 This paper deals with optimal power allocation for channel estimation of orthogonal frequency-division multiplexing uplinks in time-varying channels. In the existing literature, the estimation of time-varying channel response in an uplink environment can be accomplished by estimating the corresponding channel parameters. Ac...

In this letter, we propose an efficient scheme for combining scheduling and channel allocation functions in multi-channel systems such as an orthogonal frequency division multiple access (OFDMA). In our approach, the scheduling function is embedded in the channel allocation function in an implicit manner, and the implicit scheduler only translates quality-of-service (QoS) requirements into a se...

A channel allocation algorithm includes a channel acquisition algorithm and a channel selection algorithm. Most of the previous work concentrates on the channel selection algorithm since early channel allocation algorithms simply use a centralized channel acquisition algorithm, which depends on a mobile switching center (MSC) to accomplish channel acquisition. Recently, distributed channel acqu...

For the problems brought by malicious interference in unmanned aerial vehicle (UAV) swarm network, we establish a cluster-based UAV information transmission model. We mainly consider four aspects: cluster head selection, channel allocation, power allocation and position. In order to improve backhaul rate of swarm, propose joint optimization method spectrum resource with goal maximizing sum thro...

Simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) is a promising technology that aids in achieving full-space coverage on both sides of the surface, by splitting incident signal into transmitted reflected signals. This paper investigates resource allocation problem STAR-RIS-assisted multi-carrier communication networks. To maximize system sum-rate, joint o...

Wireless networking is becoming an increasingly important and popular way of providing global information access to users on the move. One of the main challenges for seamless mobility is the availability of simple and robust Channel Allocation algorithm. The radio propagation environment and related handoff challenges are different in cellular structures. A handoff algorithm with fixed paramete...

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...

In this paper, we study resource allocation and adaptive modulation in SC-FDMA which is adopted as the multiple access scheme for the uplink in the 3GPP-LTE standard. A sum-utility maximization (SUmax), and a joint adaptive modulation and sum-power minimization (JAMSPmin) problems are considered. Unlike OFDMA, in addition to the restriction of allocating a sub-channel to one user at most, the m...

In this paper, we study resource allocation and adaptive modulation in SC-FDMA which is adopted as the multiple access scheme for the uplink in the 3GPP-LTE standard. A sum-utility maximization (SUmax), and a joint adaptive modulation and sum-cost minimization (JAMSCmin) problems are considered. Unlike OFDMA, in addition to the restriction of allocating a sub-channel to one user at most, the mu...

Cognitive Radio (CR), which aims to improve spectrum utilization by accessing the spectrum originally licensed to a primary system, is a promising concept. In cognitive radio system based on orthogonal frequency division multiplexing (OFDM), the optimized algorithms for sub-carrier power allocation share the problems of complex iterative calculation and difficult realization. In this case, a su...