Software Design of CDMA based MAC Scheme for Microsatellite

Abstract

CDMA (Code Division Multiple Access) technology allows many users to access the medium concurrently. The store and forward (S&F) payload is to provide message relay service for terrestrial users with simple ground terminals. The widespread method of MAC (Medium Access Control) in S&F payload is ALOHA and it has poor channel throughput efficiency. This can be improved using CDMA based MAC. In this paper, two methods of code assignment namely, static & dynamic are considered. Their design methodologies and corresponding performance measures are discussed. The performance of the proposed CDMA MAC is compared with the existing ALOHA MAC and the results are presented.

Indexing terms:

• CDMA
• MAC
• Store and forward payload
• Code assignment
• Satellite
• RTOS

Additional information

Notes on contributors

T Arokia Ramya

Arokia Ramya T received her Bachelor of Enginneering (Computer Science) from Mepco Schlenk Engineering College, Madurai Kamaraj of University, Tamil Nadu and Master of Engineering (Electronics) from Madras Institute of Technology, Anna University, Tamil Nadu. She has contributed for the development of software for Store & Forward payload. Currently working as a Software Engineer in Infosys Technologies Limited, Mahindra City, Chennai, Tamil Nadu.

V Vaidehi

V Vaidehi received her BE (ECE) from College of Engineering, Guindy and ME (Electronics) and PhD from Madras Institute of Technology, Anna University. She has joined MIT in 1982 after serving IISc for a year. She is currently a Professor in Electronics department. She has done funded projects on Real Time GPS signal Simulator, Tracking Algorithms for Ship Borne Radars, Parallel Processing solutions for ADSP algorithms. She is the Task Team Member of Micro satellite development project and developed a software for Store and forward payload. She is the coordinator for the project on Design and Development of a Semantic Intrusion Detection System and Semantic Caching in Query based Networks funded by Xambala Incorporated. She is also co-coordinator of Free Open Source Software (FOSS) project. She has guided several PhD, MS, ME students and published several papers in journals and conferences. She was a recipient of Association of Commonwealth Universities (ACU) Academic Exchange fellowship.

C Ramesh

Ramesh C received BE degree in Electronics and Communication Engineering in Bharathiyar University and MTech degree in Advanced Communication Systems from SASTRA University. He is currently working towards his PhD in the area of Channel estimation in OFDM systems. He has published 2 Journal papers and more than 6 papers in various National/ International conferences.

His research interests include wireless communication and Adaptive signal processing.

R Srinivasan

R Srinivasan received his BE (ECE) from University of Madras, ME (Applied Electronics) from Madurai Kamaraj University, and presently pursuing his PhD from Anna University. He worked as Project Associate in the Microsatellite Project of Anna University from June 2003 to February 2006. He had published several papers in journals and conference proceedings. His areas of interest include Multicast Networking, Network Security and VoIP.

B Swetha

Swetha Balasubramanyam received her BE in Electronics and Communication Engineering from St Peter's Engineering College, University of Madras in 2003. She has worked as a project associate in MICSAT project at the Centre for Aero Space Research of MIT campus, Anna University.