alamouti.rar_alamouti ofdm_alamouti ofdm matlab_alamouti-mimo-OF

warning off; %Compile-time maximum values; used to set precision of control logic values max_OFDM_symbols = 2047; max_num_subcarriers = 64; max_CP_length = 16; max_num_baseRateSymbols = 31; max_num_trainingSymbols = 15; %Hard-coded OFDM parameters for now; these might be dynamic some day numSubcarriers = 64; CPLength = 16; %Set SISO mode %tx_SISO_Mode = 1; tx_alamouti_mode = 1; %Enable dynamic modulation support dynamicModulationEn = 0; %Cyclic Redundancy Check parameters CRCPolynomial = hex2dec('04c11db7'); CRC_Table = CRC_table_gen(CRCPolynomial); %Define the preamble which is pre-pended to each packet %These long and short symbols are borrowed from the 802.11a PHY standard shortSymbol_freq = [0 0 0 0 0 0 0 0 1+i 0 0 0 -1+i 0 0 0 -1-i 0 0 0 1-i 0 0 0 -1-i 0 0 0 1-i 0 0 0 0 0 0 0 1-i 0 0 0 -1-i 0 0 0 1-i 0 0 0 -1-i 0 0 0 -1+i 0 0 0 1+i 0 0 0 0 0 0 0].'; shortSymbol_time = ifft(fftshift(shortSymbol_freq)); shortSymbol_time = shortSymbol_time(1:16).'; longSymbol_freq_bot = [0 0 0 0 0 0 1 1 -1 -1 1 1 -1 1 -1 1 1 1 1 1 1 -1 -1 1 1 -1 1 -1 1 1 1 1]'; longSymbol_freq_top = [1 -1 -1 1 1 -1 1 -1 1 -1 -1 -1 -1 -1 1 1 -1 -1 1 -1 1 -1 1 1 1 1 0 0 0 0 0]'; longSymbol_freq = [longSymbol_freq_bot ; 0 ; longSymbol_freq_top]; longSymbol_time = ifft(fftshift(longSymbol_freq)).'; %Concatenate 10 short symbols together shortsyms_10 = repmat(shortSymbol_time,1,10); %Concatenate and cyclicly extend two long symbols %longsyms_2 = [longSymbol_time(33:64) repmat(longSymbol_time,1,2)]; %longSymbol_time = linspace(-1/6, 1/6, 64); %longsyms_2 = [longSymbol_time(end-31:end) repmat(longSymbol_time,1,2)]; longsyms_2 = [repmat(longSymbol_time,1,2) longSymbol_time(1:32)]; %Scale the resulting time-domain preamble to fit [-1,1] preamble = 6*[0 shortsyms_10 longsyms_2]; %randseed(1); %preamble = 6*[0 complex(randn(1,160),randn(1,160)).*0.01 longsyms_2]; preamble_I = real(preamble);%[+1*ones(1,length(preamble)-1) -0.1]; preamble_Q = imag(preamble);%[-1*ones(1,length(preamble)-1) +0.1]; %Configure the pilot tone registers pilot1_indicies = 7 + ( (64-7) * 2^16); pilot2_indicies = 21 + ( (64-21) * 2^16); %pilotValue_pos = hex2dec('7FFF') + (2^16 * hex2dec('7FFF'));%+0.9; %pilotValue_neg = hex2dec('8000') + (2^16 * hex2dec('8000'));%-0.9; pilotValue_pos = hex2dec('7FFF') + (2^16 * 0);%+0.9; pilotValue_neg = hex2dec('8000') + (2^16 * 0);%-0.9; %Training sequence, borrowed from 802.11a train = [0 -1 1 -1 1 -1 1 -1 1 -1 -1 -1 -1 1 1 -1 1 1 1 1 1 -1 -1 1 1 -1 -1 0 0 0 0 0 0 0 0 0 0 0 1 -1 1 1 1 -1 -1 -1 -1 1 1 -1 1 -1 1 1 -1 1 1 1 -1 -1 -1 -1 -1 -1]; train = train * -1; train(22) = -1; train(58) = 1; %MIMO training; use the same sequence for both antennas train = [train train]; %Maximum number of bytes per packet RAM_init_size = 4096; %Standard 48-active subcarriers subcarrier_masks = ones(1,numSubcarriers); subcarrier_masks(1)=0; %DC tone at Xk=0 subcarrier_masks(8)=0; %pilot tone at Xk=7 subcarrier_masks(22)=0; %pilot tone at Xk=21 subcarrier_masks(44)=0; %pilot tone at Xk=43 subcarrier_masks(58)=0; %pilot tone at Xk=57 subcarrier_masks([28:32])=0; %zeros at higher frequencies subcarrier_masks([33:38])=0; %zeros at higher frequencies %Choose the modulation schemes to use for the base-rate and full-rate symbols %Replcae the "2" with one of [0,2,4,6,8] to use 0, QPSK, 16/64/256 QAM modulation_antA = 2*subcarrier_masks; modulation_antB = 2*subcarrier_masks; modulation_baseRate = 2*subcarrier_masks; %Final vector must be: [AntennaA AntennaB BaseRate] %AntA = AntB = BaseRate = 48 non-zero subcarriers -> 12 bytes/OFDM symbol with QPSK subcarrier_QAM_Values = [modulation_antA modulation_antB modulation_baseRate]; numBytes_BaseRateOFDMSymbol = sum(modulation_baseRate)/8; numBytes_FullRateOFDMSymbol = sum(modulation_antA)/8; %Example of how modulation data gets formatted as bytes in the packet's header; useed for simulation subcarrier_QAM_Values_bytes = reshape([modulation_antA modulation_antB], 2, numSubcarriers); subcarrier_QAM_Values_bytes = sum(subcarrier_QAM_Values_bytes .* [ones(1,64).*2^4; ones(1,64)]); %Setup the packet length for simulation numTrainingSymbols = 2; %numFullRateSymbols = ceil(120/12);%124; numBaseRateSymbols = 0; if(dynamicModulationEn == 1) %4 bits per subcarrier, 64 subcarriers on 1 antenna -> 32 bytes for mod data end %Setup the packet contents rand('state',1); %Get the same packet each time for BER testing %Define the packet's header & other meta-information pkt_MACAddr_RX = randint(1,6,255); %Radnom MAC addresses pkt_MACAddr_TX = randint(1,6,255); pkt_version = 1; pkt_rate = 2; pkt_pktType = 0; pkt_reserved = [0 0 0 0 0 0]; % 6 bytes %Leave 32 bytes of extra space pkt_dynModulation = zeros(1,32); %Zero-padding to make sure only header information ends up in base-rate symbols pkt_zeroPad = zeros(1,numBytes_BaseRateOFDMSymbol - mod(length(pkt_dynModulation),numBytes_BaseRateOFDMSymbol)); %Calculate the number of bytes in the packet, based on the number of OFDM symbols specified above % In hardware, the user code will provide this value per-packet pkt_numPayloadBytes = 1400;%numBytes_BaseRateOFDMSymbol*numBaseRateSymbols + numBytes_FullRateOFDMSymbol*numFullRateSymbols; numFullRateSymbols = ceil(pkt_numPayloadBytes/numBytes_FullRateOFDMSymbol);%124; numFullRateSymbols = numFullRateSymbols + mod(numFullRateSymbols, 2); %Construct the packet header (base-rate symbol data) byte-by-byte packetHeader = [... pkt_MACAddr_RX... %bytes 0-5 pkt_MACAddr_TX... %bytes 6-11 pkt_version... %byte 12 pkt_rate... %byte 13 pkt_pktType... %byte 14 0 ... %byte 15 floor((pkt_numPayloadBytes/256))... %byte 16 mod(pkt_numPayloadBytes,256)... %byte 17 pkt_reserved... %bytes 18-23 ]; %If dynamic modulation is enabled, be sure the header has room for the modulation bytes if(dynamicModulationEn == 1) packetHeader = [packetHeader pkt_dynModulation pkt_zeroPad]; end %Assemble the rest of the packet, using random bytes for the full-rate payload packet = [packetHeader 1:-4+(numBytes_FullRateOFDMSymbol*numFullRateSymbols)]; %packet = [packetHeader randint(1,(pkt_numPayloadBytes-4-24),255)];%1:(pkt_numPayloadBytes-4-24)]; %Add the 32-bit checksum to the end of the payload % In hardware, the checksum automatically over-writes the last four bytes of the payload packet = mod(packet,256); packet = [packet calcTxCRC(packet)]; %This value allows the simulated transmitter to start new packets % leaving a few hundred cycles of idle time between each packet simOnly_numSamples = length(preamble)+( (numSubcarriers+CPLength)*(numTrainingSymbols + numBaseRateSymbols + numFullRateSymbols) ); %Define the indicies (zero-indexed, like C) of some important bytes in the header byteIndex_rate = 13; byteIndex_version = 12; %byteIndex_numPayloadBytes = [16 17]; byteIndex_numPayloadBytes = [22 23]; byteIndex_dynModulationStart = 24; %Parameters to initialize the packet buffers % The default packet is loaded at configuration, allowing real-time BER tests % This packet will be overwritten in hardware when user-code loads packets packet_length = length(packet)-1; RAM_init_values = [packet, zeros(1,RAM_init_size-1-packet_length)]; BER_RAM_init_values = reshape(flipud(reshape(RAM_init_values, 8, RAM_init_size/8)), 1, RAM_init_size); %LSFR parameters, used for random payload mode txLSFR_numBits = 13; txLSFR_polynomials = {'21' '35' '0B' '1D' '35' '0B' '3D' '2B'}; txLSFR_initValues = {'3F' '1B' '03' '35' '17' '0A' '74' '39'}; %Precision for the constants which store the modulation values modConstellation_prec = 8; modConstellation_bp = 7; TxRx_FFTScaling = bin2dec('011010') + (bin2dec('000101') * 2^6); %Defintion of the various constellations %Gray coded bit-symbol mappings %Borrowed from the IEEE 802.16 specification % IEEE Std 802.16-2004 Tables 153-155 (pg. 329) %QPSK constellation