invphasemap.m

simulation module for visual wireless sensor network

function [BitVector] = InvPhaseMap(Phase)

% Just an example.. You should define your own inverse phase map based on 
% the Phase mapping that you have defined. This scheme works for the demo
% phase map that is provided with the code. 
%
% Guidelines
% -----------
% In general you have to do a  Maximum Likelihood decoding (or minimum 
% distance decoding) of the received symbols to decide on the input 
% bits that were transmitted. For example, in the case of I/Q modulation,
% the way to proceed is as follows :
% 1. Find the sine and cosine of the angle. This gives your constellation
% point on the I/Q space.
% 2. Now, find the Euclidean Distance between the received point and all
% the possible constellation points.
% 3. The Constellation point that is 'nearest' to the received point (or 
% the one which gives the minimum distance) is the decoded constellation
% point and the bit vector corresponding to that constellation point is the
% decoded bitvector.

BitVector(1) = sin(Phase)<0;
BitVector(2) = cos(Phase)<0;