Cedric Roux
56c66c09aa
Pre-ci test passed git-svn-id: http://svn.eurecom.fr/openair4G/trunk@4000 818b1a75-f10b-46b9-bf7c-635c3b92a50f
44 lines
952 B
Matlab
44 lines
952 B
Matlab
function idx = get_codebook_idx(H,Codebook,bit_vec)
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% Hq = quantize_H(H, codebook)
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%
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% This function quantizes H according to the given codebook
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%
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% Parameters:
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% H [N_Tx x N_User] Channel matrix to be quatized
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% codebook [N_Tx x N_codes x N_User] Codebook
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[N_Tx, N_User] = size(H);
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N_codes = size(Codebook,2);
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if size(Codebook,1) ~= N_Tx
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error('codebook must be of size [N_Tx x N_codes x N_User]');
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end
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if size(Codebook,3) ~= N_User
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error('codebook must be of size [N_Tx x N_codes x N_User]');
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end
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if pow2(bit_vec(end)) > N_codes
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error('pow2(bit_vec) must be < than N_codes')
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end
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% normalize the channel
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for k=1:N_User
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normH(k) = norm(H(:,k));
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H(:,k) = H(:,k)./norm(H(:,k));
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end
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d = zeros(N_codes,N_User);
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for k=1:N_User
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for i=1:N_codes
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d(i,k) = Codebook(:,i,k)'*H(:,k);
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end
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end
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% plot(abs(d))
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for b=1:length(bit_vec)
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[m,idx(b,:)] = max(abs(d(1:pow2(bit_vec(b)),:)),[],1);
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end
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