1

Study and Simulation of Concatenated Codes

Saleh Faruque

Radio Network Planning

Wireless Systems Engineering, NORTEL

P.O. Box 833871, Mail Stop: 992/02/E60

Richardson, Tx 75083-3871

Phone: (972) 684-5981

Fax: (972) 685-3463

E-mail:

PROJECT OUTLINE

Concatenated coding, originally developed by Forney [1] is well known for their excellent error control properties. A simple concatenated code, based on two codes in series [2-5], can be constructed as shown in Fig.1. Here, the high-speed user data is first encoded by means of an outer code, typically a block code such as Reed Solomon code. Next, the data and parity bits resulting from the outer code are interleaved and encoded by a rate ½ or rate ¾ Convolutional encoder inner code. The encoded bit stream is then modulated and transmitted through a channel.


Fig.1. Concatenated Coding Scheme based on Block outer code and convolutional inner code.

On the receive side, the impaired code is first decoded by an inner decoder, typically a Viterbi decoder, de--interleaved and then by an outer decoder (typ. RS).

The essential feature of the concatenated coding scheme is that any errors which do not get detected by the inner code is corrected by the outer code.

Objectives of this Project

1.  Study:

Investigate the error control properties of Concatenated coding with RS-outer code and Convolutional/Viterbi inner code with the following parameters:

Convolutional Inner Code:

-  Rate: ½, ¾

-  Constraint length 7

RS- Outer Code:

-  Parameters: Will be supplied later

2.  Simulation:

Simulate the Concatenated coding scheme by means of a commercially available simulation platform (TBD) and Obtain BER vs. Eb/No Curves for r=1/2 and 3/4

3.  Report:

Submit a technical report

Deliverables: A technical report compiling: Literature survey, Simulation, BER vs. Eb/No curves.

The results of this simulation task would publishable in technical journals or conferences. If you are interested in being pointed to the proper venues, assistance in submitting a paper or interested in Co-Authoring a paper, please contact me.

References

[1] G.D. Forney, Jr., “Concatenated Codes, MIT Press, Cambridge, Mass., 1966

[2] Shu Lin et. Al., “Error Control Coding; Fundamentals and Applications”, Prentice Hall, 1983

[3] George C. Clark. et. al., “Error Correction Coding for Digital Communications”, Plenum press, 1981

[4] Bernard Sklar, “Digital Communications Fundamentals and Applications”, Prentice Hall, 1988

[5] John G. proakis, “Digital Communications”, McGraw-Hill, 1995