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This paper proposed a more realistic imperfect power control model for Signal-to-interference radio (SIR)-based call admission control algorithms comparing with the previous method in CDMA systems. A new call is accepted by a base station if the measured SIR can be guaranteed based on our proposed model. Similarly, we considering the voice, data multimedia traffic services, etc. The simulation results...
In this paper, we propose a novel algorithm to remove secondary users (SUs) in a Cognitive Radio (CR) CDMA network to maintain a predefined interference threshold at BS. Specifically, we develop a simulation test bed for analyzing performances of a CR user and a primary user (PU) in a single cell. CR users or SUs are assumed to form pair wise link in an infrastructure less ad hoc network that coexists...
The objective of the present paper is to propose a rapid and accurate method for the evaluation of the quality of service (QoS) perceived by the users in the uplink of wireless cellular networks. In doing so we aim to account for the dynamics induced by the arrivals and the departures of the users. In particular, the QoS is evaluated in terms of the blocking probability for streaming users and the...
We consider the problem of cognitive code-division channelization (simultaneous power and code-channel allocation) for secondary transmission links co-existing with an unknown primary code-division multiple-access (CDMA) system. We first develop a blind primary-user identification scheme to detect the binary code sequences (signatures) utilized by primary users. To create a secondary link we propose...
In this paper, we study the dynamic uplink power allocation problem in a multi-cell multi-user CDMA-based cellular cognitive radio (CR) system, in which the concept of hierarchical interference bound is introduced to describe the coexistence of the multi-user interference. We propose a novel differential game-based dynamic power allocation model via two formulated cost functions. Furthermore, we present...
Call Admission control (CAC) is an important part of radio resource management (RRM) according to certain criteria, CAC determines whether the call is admitted to access or not. CAC is an important means to guarantee the quality of service (QoS) in wireless network. This paper analyses the multi-user detection factor on the uplink load of TD-SCDMA system and the effects of adjacent cell interference...
In this paper, a simulation study has been carried out to evaluate performance of joint admission and power control (JAPC) algorithms in Cognitive - CDMA Networks. Performance has been evaluated for SU in an uplink scenario of CDMA network consisting primary user (PU) and secondary user (SU). A numbers of algorithms have been investigated. Long term fading has been assumed in addition to path loss...
This paper extends the discrete Verhulst power equilibrium method, previously suggested in to the power-rate optimal allocation problem. Multirate users associated with different types of traffic are aggregated to distinct user' classes, with the assurance of target rate allocation per user and QoS. Therein, single-rate Verhulst power allocation algorithm was adapted to the multirate DS/CDMA power...
This paper proposes a game-theoretic approach to the problem of resource allocation for a CDMA wireless communication network, focusing on code synchronization. To capture the tradeoff between obtaining good synchronization performance and saving as much energy as possible, we propose a noncooperative game in which each pair transmitter-receiver in the network seeks to maximize the ratio of the probability...
Power control is one of the major parts of cellular communication system. The power control helps maintain quality of service of the communication link. In this paper, a simple proportional integral (PI) control is used in the Code Division Multiple Access (CDMA) radio system to maintain the signal to noise ratio (SNR) around a desired level under channel fading environment with multiple access interference...
In radio mobile cellular networks, the users located at the cell border are suffering from a bad quality of service (QoS). Cooperative communications is a promising technique that can overcome this weakness by allowing the users to profit from powerful benefits of the spatial diversity. Nevertheless, abstraction is usually made on the impact of the additional multiple access interference inherent...
The number of users accepted by a cell is limited by the total received interference power at base station transceiver in code-division multiple access (CDMA) system. In this paper, we propose a received power based call admission control (MSRP-CAC) scheme supporting multi-class services for uplink, which determines the admission of multi-class services via presetting power allocation ratios. The...
In this paper, we propose an uplink call admission control (CAC) scheme for WCDMA. The proposed scheme employs two-stage bit rate degradation strategies to reduce the total number of interference in order to increase the achievable SIR of the to-be-admit call especially in congested situation. The proposed scheme has shown improvement in the QoS performance by reducing the percentage of blocked calls...
Call access control (CAC) is one of the most important parts in wireless communication network resource management. The system allow or refuse the access according to certain standards of CAC strategy decision. It will have a direct impact on the performance of the network and resources utilization. In cdma system there is a algorithm based on a comparison of access control, but this strategy is in...
Multihop communication has been proposed in cellular networks to overcome some inherent limitations. Congestion relief is amongst the promised gains. In this paper, the concept of inter-cell relay, which uses multihop communication to divert calls from heavy loaded cells to less loaded adjacent cells, is introduced. We show that using inter-cell relay, the number of supported calls inside a congested...
In radio mobile cellular networks, the users located at the cell border suffer from a bad quality of service (QoS). Cooperative communication is a promising technique that can overcome this weakness by allowing these users to profit from powerful benefits of spatial diversity. Nevertheless, abstraction is usually made on the impact of the additional multiple access interference inherent to relaying...
2-dimensional (2D) block spread CDMA makes it possible to achieve multiple-access interference (MAI) free uplink transmission with low-complexity single-user detection and therefore is very attractive. In this paper, we propose a code assignment algorithm for 2D block spread CDMA uplink in multi-cell systems. It is shown by the computer simulation that in the frequency-selective fading channel, the...
This paper examines the effect of cell loadings on the performance of a group based multicast algorithm implemented on the HSDPA air interface. The group based multicast scheme could offer higher QoS and capacity in a HSDPA network. However, the performance of the multicast algorithm could be affected by neighboring cell loadings. In order to compensate the variable SINR conditions caused by the variation...
Compensation for near-far effects is critical for error performance of a direct sequence code-division multiple-access system. In this paper, we intend to explore the potential of power control to overcome fading and near-far effect in a cooperative wideband time-division duplex CDMA (TDD-CDMA) network. An effective power control scheme of multiple-access relay channel is presented to provide all...
In this era of perpetual connectivity, with the introduction of new data-intensive real-time applications such as video-conferencing, video-on-demand, and interactive gaming, the need for doing more with limited network resources has become more than ever before. The continuous drive toward the notion of pervasive computing and communication requires a shift toward more adaptive and collaborative...
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