Code-hopping as a new strategy to improve performance of S-CDMA cellular systems

Date

1996-11-22

Author

Unal, B
Tanik, Y

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

45
views

0
downloads

An alternative coding strategy to the fixed spreading code assignment of code-division multiple-access (CDMA) systems, called code-hopping is proposed for the uplink path of synchronous CDMA (S-CDMA) systems. In code-hopping S-CDMA, mobile users swap their spreading codes according to a predetermined hopping pattern. In this way, mobile channels which are identified by the spreading codes are exchanged. Performance of code-hopping on the uplink path of S-CDMA systems is evaluated numerically on a typical S-CDMA system in the case of random hopping and compared to that of conventional S-CDMA, In performance evaluation, the criterion is the uplink outage probability which is defined as the probability of the uplink interference power exceeding a predetermined threshold. The numerical results show that application of code-hopping to the uplink communication of S-CDMA systems decreases the outage probability significantly.

URI

https://hdl.handle.net/11511/66052

DOI

https://doi.org/10.1109/GLOCOM.1996.587659

Collections

Department of Electrical and Electronics Engineering, Conference / Seminar

Suggestions

OpenMETU
Core

Capacity improvement by code-hopping in S-CDMA systems Unal, B; Tanik, Y (1998-06-11) Code-hopping, which is an alternative spreading strategy to the static spreading code assignment of CDMA systems, is evaluated as a method to combat multiuser interference in S-CDMA systems. Uplink capacities of conventional and code-hopping S-CDMA are determined and compared by simulations carried out on a typical S-CDMA system for three nondispersive channels : No-fading, Rayleigh fading and Rician fading. The cellular structure is not composed of regular hexagons, but irregularly shaped natural cells whe...
Data sharing using mqtt and zigbee-based dds on resource-constrained contiki-based devices Yıldırım, Tunahan; Oğuztüzün, Mehmet Halit S.; Department of Computer Engineering (2020) This thesis describes the implementation of data sharing among resource-constrained IoT devices using two different middleware: MQTT(Message Queuing Telemetry Transport) and DDS (Data Distribution Services) for Real-Time Systems. In our setting, all IoT devices run under the Contiki operating system. In the configuration for DDS, a pair of Texas Instruments’ MSP430 processor-based ZigBee powered Advanticsys XM1000 device is used to realize data sharing between wireless sensor network devices without a serve...
Broadband Multilevel Fast Multipole Algorithm For Large-Scale Problems With Nonuniform Discretizations Ergül, Özgür Salih; Takrimi, Manouchehr; Erturk, Vakur B. (2016-08-18) We present a broadband implementation of the multilevel fast multipole algorithm (MLFMA) for fast and accurate solutions of multiscale problems involving highly nonuniform discretizations. Incomplete tree structures, which are based on population-based clustering with flexible leaf-level boxes at different levels, are used to handle extremely varying triangulation sizes on the same structures. Superior efficiency and accuracy of the developed implementation, in comparison to the standard and broadband MLFMA...
A P2P based failure detection model for distributed systems Kavuklu, Celal; Doğru, Ali Hikmet; Department of Computer Engineering (2006) A comprehensive failure detection model is proposed to detect service failures in asynchronous distributed systems. The proposed model takes advantage of P2P technology to provide required functionality. When compared to similar studies in failure detection, the presented failure detection model is more autonomous in resolving service dependencies, embodies more flexibility in providing different failure detection functions (like unreliable failure detectors, membership services) and offers more security. A...
Implementation of stanag 428 hf modem software on tms320c54x digital signal processor Örümlü, Erhan; Baykal, Buyurman; Department of Electrical and Electronics Engineering (2004) In this research, STANAG 4285 HF modem software is implemented on TMS320C54x fixed point digital signal processor. The software is optimized in order to meet real-time operation requirements. A fractionally spaced least mean square (LMS) decision feedback equalizer (DFE) is employed for the receiver. In order to improve the convergence of the LMS algorithm a multipass technique is utilized. Based on Watterson̕s model, an HF channel simulator is employed for evaluating the performance of the modem. The simul...

Citation Formats

B. Unal and Y. Tanik, “Code-hopping as a new strategy to improve performance of S-CDMA cellular systems,” 1996, p. 1316, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/66052.