Title :
A mobile controlled algorithm for improving the throughput in a S-ALOHA DS-CDMA system
Author :
Sallent, Oriol ; Agustí, Ramon
Author_Institution :
Dept. de Teoria del Senyal i Comunicacions, Univ. Politecnica de Catalunya, Barcelona, Spain
Abstract :
This paper presents a novel adaptive DS-CDMA slotted-ALOHA packet random access scheme with transmitter-based spreading codes for mobiles. It is aimed at improving the throughput and message delay delivery when traffic load values below the saturation point of the conventional DS-CDMA slotted-ALOHA system are sensed in the channel. For this purpose a mobile assisted algorithm is envisaged to control the change of the transmission rate according to the traffic load. This algorithm revealed that the optimum behavior, obtained using a Markov chain model, may be almost reached at a low complexity cost. Moreover, priorities between mobiles could be easily established. Finally, a traffic model based on a realistic statistical length distribution of the messages illustrates how the delay delivery can be greatly reduced
Keywords :
Markov processes; access protocols; channel capacity; code division multiple access; land mobile radio; packet radio networks; pseudonoise codes; spread spectrum communication; telecommunication traffic; DS-CDMA system; Markov chain model; S-ALOHA; adaptive technique; low complexity; message delay delivery; mobile controlled algorithm; packet random access scheme; slotted-ALOHA; statistical length distribution; throughput improvement; traffic load; transmission rate; transmitter-based spreading codes; Control systems; Cost function; Delay; Multiaccess communication; Multiple access interference; Packet radio networks; Radio spectrum management; Telecommunication traffic; Throughput; Traffic control;
Conference_Titel :
Personal, Indoor and Mobile Radio Communications, 1996. PIMRC'96., Seventh IEEE International Symposium on
Conference_Location :
Taipei
Print_ISBN :
0-7803-3692-5
DOI :
10.1109/PIMRC.1996.568472
