A new design method for optical CDMA computer networks

Muckenheim, J.; Iversen, K.

doi:10.1109/iscc.1997.616070

Cited by 6 publications

(5 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The same thinking and backlog activities have been assumed in these two figures. The code length and code weight are (31,3) and (121, 3) in Figs. 3 and 4, respectively .…”

Section: Numerical Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Optical CDMA random access protocols with and without pretransmission coordination

Shalaby

2003

J. Lightwave Technol.

View full text Add to dashboard Cite

The link layer of an optical direct-detection code-division multiple-access (CDMA) packet network is considered. Two different protocols that need pretransmission coordination are proposed. A variation of the second protocol that does not need pretransmission coordination is discussed. Both system throughput and average packet delay are derived and investigated for two different receiver models: the correlation and chip-level receivers. Both multiple-access interference and the photodetector's shot noise are taken into account in the analysis. The case where the number of users exceeds the available number of CDMA codes is numerically investigated. Our results reveal that the proposed protocols yield competitive system throughputs when used with the correlation receivers. Further, significant improvement in the throughput is achieved when using chip-level receivers along with the second protocol.

show abstract

“…The same thinking and backlog activities have been assumed in these two figures. The code length and code weight are (31,3) and (121, 3) in Figs. 3 and 4, respectively .…”

Section: Numerical Resultsmentioning

confidence: 99%

“…To obtain the steady-state throughput and average packet delay, the above system can be described by a discrete-time Markov chain [31]. The chain consists of 1 states depending on the number of backlogged users .…”

Section: Steady-state Performancementioning

confidence: 99%

Optical CDMA random access protocols with and without pretransmission coordination

Shalaby

2003

J. Lightwave Technol.

View full text Add to dashboard Cite

show abstract

“…In [4], [6] and [7] 1-D codes are used in the O-CDMA packet networks. Among several 1-D codes OOCs have the lowest out-of-phase auto-correlation and cross-correlation values, equal to 1.…”

mentioning

confidence: 99%

W/T SPR codes offer higher throughput in OCDMA networks

Shivaleela

Tangade

2011

TENCON 2011 - 2011 IEEE Region 10 Conference

View full text Add to dashboard Cite

In this paper optical code-division multiple-access (O-CDMA) packet network is considered, which offers inherent security in the access networks. Two types of random access protocols are proposed for packet transmission. In protocol 1, all distinct codes and in protocol 2, distinct codes as well as shifted versions of all these codes are used.O-CDMA network performance using optical orthogonal codes (OOCs) 1-D and two-dimensional (2-D) wavelength/time single-pulse-per-row (W/T SPR) codes are analyzed. The main advantage of using 2-D codes instead of one-dimensional (1-D) codes is to reduce the errors due to multiple access interference among different users. SPR codes are chosen as they have nearly ideal correlation properties. In this paper, correlation receiver is considered in the analysis. Using analytical model, we compare the OOC and SPR code performances in O-CDMA networks .We compute packetsuccess probability and throughput for both the types of codes. The analysis shows improved performance with SPR codes as compared to OOC codes.

show abstract

“…Muckenheim et al [16], [17] studied the effect of bit error probability on the packet error probability and suggested the use of block codes to reduce packet errors. They also described a random delay protocol to reduce the errors incurred during periods of high activity.…”

Section: Related Workmentioning

confidence: 99%

The need for media access control in optical CDMA networks

View full text Add to dashboard Cite

Abstract-Optical CDMA Local Area Networks allow shared access to a broadcast medium. Every node on the network is assigned an Optical Orthogonal Codeword (OOC) to transmit or receive on. OOCs are designed to be pseudo-orthogonal, i.e., the correlation (and therefore the interference) between pairs of codewords is constrained. This paper demonstrates that the use of optical CDMA does not preclude the need for a media access control (MAC) layer protocol to resolve contention for the shared media.OOCs have low spectral efficiency. As more codewords are transmitted simultaneously, the interference between codewords increases and the network throughput falls. This paper analyzes a network architecture where there is virtually no MAC layer, except for choice of the codeset, and shows that its throughput degrades and collapses under moderate to heavy load. We propose an alternate architecture called Interference Avoidance where nodes on the network use media access mechanisms to avoid causing interference on the line, thereby improving network throughput. Interference avoidance is analyzed and it is shown that it can provide up to 30% improvement in throughput with low delays and no throughput collapse. We validate our analysis through simulation with realistic network traffic traces.

show abstract

A new design method for optical CDMA computer networks

Cited by 6 publications

References 12 publications

Optical CDMA random access protocols with and without pretransmission coordination

Optical CDMA random access protocols with and without pretransmission coordination

W/T SPR codes offer higher throughput in OCDMA networks

The need for media access control in optical CDMA networks

Contact Info

Product

Resources

About