Blahut-Arimoto Algorithm for Action-dependent Feedback (BAA-Action)

 

About

The software BAA-Action, is a matlab package which computes the maximum of normalized directed information for finite state channels with states known to the decoder, when the encoder takes cost constrained actions to determine whether or not the state is fed back to the encoder. Specifically the following quantity is evaluated for the figure shown above, C_N(Gamma)=maxfrac{1}{N}I(X^Nrightarrow Y^N) where maximum is over causal conditioning distribution r(x^N,a^Nparallel z^{N-1}) such that the cost constraints on actions are satisfied. Please refer to the Section XI-A in the reference for more details. The software is specifically coded for the example in Section XI-B of the paper, where the channel is Markovian, all channel input symbols, output symbols and states being binary.

The Blahut-Arimoto Algorithm for Action-Dependent Feedback (BAA-Action) is as follows.

 

Installation and Execution

The matlab package can be found here. You will also need CVX package.
The software contains

 

Reference

1. To Feed or Not to Feed Back
Himanshu Asnani, Haim Permuter, Tsachy Weissman, submitted to IEEE Transactions on Information Theory, Nov 2010.
A shorter version to appear in Proceedings of 2011 IEEE Interational Symposium on Information Theory, St. Petersburg, Russia, August 2011. (slides) (ISIT STUDENT PAPER AWARD FINALIST)

Acknowledgement

The work has been supported by the NSF Award-1049413.

Contact

Himanshu Asnani
Email : asnani AT stanford.edu