[1671] | 1 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 2 | % Spectrum sensing using WARPLab |
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| 3 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 4 | % The specific steps implemented in this script are the following |
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| 5 | |
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| 6 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 7 | % Instructors code |
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| 8 | |
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| 9 | % 0. Initializaton and definition of parameters |
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| 10 | % 1. Generate a sum of two sinusoids to transmit |
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| 11 | % 2. Plot the transmitted data fft and waveform |
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| 12 | % 3. Prepare WARP node for transmission |
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| 13 | % 4. Disable the transmitter path |
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| 14 | |
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| 15 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 16 | |
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| 17 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 18 | % Attendees code |
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| 19 | |
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| 20 | % The specific steps implemented in this script are the following |
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| 21 | % 0. Initialization and definition of parameters |
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| 22 | % 1. Prepare the WARP node for reception (sensing the medium) and send trigger to |
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| 23 | % start reception (trigger is the SYNC packet) |
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| 24 | % 2. Read the received samples from the WARP node |
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| 25 | % 3. Reset and disable the WARP node |
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| 26 | % 4. Compute and plot the fft of the received data |
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| 27 | % 5. Plot the received waveform |
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| 28 | % 6. Compute the Received Signal Strength Indicator (RSSI in dBm) of the received signal |
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| 29 | % 7. Close sockets |
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| 30 | |
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| 31 | % In this lab exercise you will write a matlab script that implements the |
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| 32 | % steps above. Part of the code is provided, some part of the code you |
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| 33 | % will write. Read the code below and fill in with your code wherever you |
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| 34 | % are asked to do so. |
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| 35 | |
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| 36 | % WARPLab documentation can be found online at |
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| 37 | % http://warp.rice.edu/trac/wiki/WARPLab |
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| 38 | |
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| 39 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 40 | |
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| 41 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 42 | % 0. Initializaton and definition of parameters |
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| 43 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 44 | |
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| 45 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 46 | % Instructors and attendees code |
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| 47 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 48 | |
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| 49 | %Load some global definitions (packet types, etc.) |
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| 50 | warplab_defines |
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| 51 | |
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| 52 | % Create Socket handles and intialize nodes |
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| 53 | [socketHandles, packetNum] = warplab_initialize(2); |
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| 54 | |
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| 55 | % Separate the socket handles for easier access |
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| 56 | % The first socket handle is always the magic SYNC |
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| 57 | % The rest of the handles are the handles to the WARP nodes |
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| 58 | udp_Sync = socketHandles(1); % SYNC |
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| 59 | udp_node1 = socketHandles(2); % Handle for node 1: Receiver node |
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| 60 | udp_node2 = socketHandles(3); % Handle for node 2: Transmitter node |
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| 61 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 62 | |
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| 63 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 64 | % Instructors code |
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| 65 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 66 | |
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| 67 | % Define WARPLab parameters. |
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| 68 | TxDelay = 0; % Number of noise samples per Rx capture. In [0:2^14] |
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| 69 | TxLength = 2^14-1-TxDelay; % Length of transmission. In [0:2^14-1-TxDelay] |
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| 70 | Node2_CarrierChannel = 1; % Channel in the 2.4 GHz band. In [1:14] |
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| 71 | Node2_Radio2_TxGain_BB = 3; % Tx Baseband Gain. In [0:3] |
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| 72 | Node2_Radio2_TxGain_RF = 40; % Tx RF Gain. In [0:63] |
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| 73 | TxMode = 0; % Transmission mode. In [0:1] |
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| 74 | % 0: Single Transmission |
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| 75 | % 1: Continuous Transmission. Tx node will continue |
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| 76 | % transmitting the vector of samples until the user manually |
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| 77 | % disables the transmitter. |
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| 78 | |
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| 79 | % Download the WARPLab parameters to the WARP nodes. |
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| 80 | warplab_writeRegister(udp_node2,TX_DELAY,TxDelay); |
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| 81 | warplab_writeRegister(udp_node2,TX_LENGTH,TxLength); |
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| 82 | warplab_setRadioParameter(udp_node2,CARRIER_CHANNEL,Node2_CarrierChannel); |
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| 83 | % Node 2 will be set as the transmitter so download Tx gains to node 2. |
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| 84 | warplab_setRadioParameter(udp_node2,RADIO2_TXGAINS,(Node2_Radio2_TxGain_RF + Node2_Radio2_TxGain_BB*2^16)); |
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| 85 | warplab_writeRegister(udp_node2,TX_MODE,TxMode); |
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| 86 | |
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| 87 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 88 | % Attendees code |
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| 89 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 90 | |
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| 91 | % Define WARPLab parameters for this workshop exercise. |
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| 92 | |
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| 93 | %-------------------------------------------------------------------------% |
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| 94 | % USER CODE HERE |
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| 95 | |
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| 96 | % - Create a variable named 'Node1_SensingChannel' and assign a value to |
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| 97 | % this variable . |
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| 98 | % - Variable 'Node1_SensingChannel' can be any integer value in [1:14] range. |
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| 99 | % - The value of Node1_SensingChannel specifies a channel in the 2.4 GHz band |
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| 100 | % and this is the channel at which sensing wll be centered |
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| 101 | |
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| 102 | Node1_SensingChannel = 1; |
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| 103 | %-------------------------------------------------------------------------% |
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| 104 | |
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| 105 | %-------------------------------------------------------------------------% |
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| 106 | % USER CODE HERE |
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| 107 | |
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| 108 | % - Set the sensing channel of node 1 by using the 'warplab_setRadioParameter' |
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| 109 | % function and the 'Node1_SensingChannel' variable just defined |
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| 110 | |
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| 111 | % The 'warplab_setRadioParameter' function has three arguments which are specified below: |
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| 112 | %(The arguments in the 'warplab_setRadioParameter' function do not use the quotes '') |
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| 113 | |
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| 114 | % 1. The first argument of the 'warplab_setRadioParameter' function identifies the |
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| 115 | % node where the radio parameter will be set. The id or handle to node 1 is |
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| 116 | % 'udp_node1'. |
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| 117 | |
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| 118 | % 2. The second argument of the 'warplab_setRadioParameter' function identifies the |
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| 119 | % radio parameter that will be set. The sensing channel is the receiver center |
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| 120 | % frequency or carrier channel. To set the sensing channel, the radio |
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| 121 | % parameter that needs to be set is the parameter identified as |
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| 122 | % 'CARRIER_CHANNEL'. |
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| 123 | |
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| 124 | % 3. The third argument of the 'warplab_setRadioParameter' function is the channel |
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| 125 | % number to be set. Use as third argument the variable 'Node1_SensingChannel' |
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| 126 | % that you have previously defined |
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| 127 | |
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| 128 | warplab_setRadioParameter(udp_node1,CARRIER_CHANNEL,Node1_SensingChannel); |
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| 129 | %-------------------------------------------------------------------------% |
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| 130 | |
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| 131 | %-------------------------------------------------------------------------% |
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| 132 | % USER CODE HERE |
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| 133 | |
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| 134 | % - Create a variable named 'Node1_Radio2_RxGain_BB' and assign a value to |
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| 135 | % this variable . |
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| 136 | % - Node1_Radio2_RxGain_BB can be any integer value in [0:31] range. |
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| 137 | % - Node1_Radio2_RxGain_BB is the baseband gain applied by the receiver. |
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| 138 | % - Each unit step increase in the value of Node1_Radio2_RxGain_BB |
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| 139 | % corresponds to a 2 dB increase of gain applied to the received signal. |
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| 140 | |
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| 141 | Node1_Radio2_RxGain_BB = 9; |
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| 142 | %-------------------------------------------------------------------------% |
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| 143 | |
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| 144 | |
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| 145 | %-------------------------------------------------------------------------% |
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| 146 | % USER CODE HERE |
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| 147 | |
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| 148 | % - Create a variable named 'Node1_Radio2_RxGain_RF' and assign a value to |
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| 149 | % this variable . |
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| 150 | % - Node1_Radio2_RxGain_RF can be any integer value in [1:3] range. |
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| 151 | % - Node1_Radio2_RxGain_RF is the RF gain applied by the receiver. |
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| 152 | % - Each unit step increase in the value of Node1_Radio2_RxGain_RF |
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| 153 | % corresponds to a 15 dB increase of gain applied to the received signal. |
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| 154 | |
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| 155 | Node1_Radio2_RxGain_RF = 2; |
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| 156 | %-------------------------------------------------------------------------% |
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| 157 | |
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| 158 | % Set the baseband and RF receiver gains of the radio by using the 'warplab_setRadioParameter' |
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| 159 | % function and the 'Node1_Radio2_RxGain_BB' and 'Node1_Radio2_RxGain_RF' variables just defined |
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| 160 | warplab_setRadioParameter(udp_node1,RADIO2_RXGAINS,(Node1_Radio2_RxGain_BB + Node1_Radio2_RxGain_RF*2^16)); |
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| 161 | |
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| 162 | Node1_MGC_AGC_Select = 0; % Set MGC_AGC_Select=1 to enable Automatic Gain Control (AGC). |
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| 163 | % Set MGC_AGC_Select=0 to enable Manual Gain Control (MGC). |
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| 164 | % By default, the nodes are set to MGC. |
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| 165 | % Set MGC mode in Rx node |
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| 166 | warplab_setAGCParameter(udp_node1,MGC_AGC_SEL,Node1_MGC_AGC_Select); |
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| 167 | |
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| 168 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 169 | % Instructors code : |
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| 170 | % 1. Generate a sum of two sinusoids to transmit |
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| 171 | % 2. Plot the transmitted data fft and waveform |
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| 172 | % 3. Prepare WARP node for transmission |
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| 173 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 174 | |
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| 175 | % 1. Generate a sum of two sinusoids to transmit |
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| 176 | |
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| 177 | % Create a signal to transmit, the signal is a function of the time vector |
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| 178 | % 't' the signal can be real or complex. |
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| 179 | % The signal must meet the following requirements: |
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| 180 | % - Signal to transmit must be a row vector. |
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| 181 | % - The amplitude of the real part must be in [-1:1] and the amplitude |
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| 182 | % of the imaginary part must be in [-1:1]. |
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| 183 | % - Highest frequency component is limited to 9.5 MHz (signal bandwidth |
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| 184 | % is limited to 19 MHz) |
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| 185 | % - Lowest frequency component is limited to 30 kHz |
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| 186 | |
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| 187 | t = 0:(1/40e6):TxLength/40e6 - 1/40e6; % Create time vector. |
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| 188 | f1 = 1e6; |
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| 189 | f2 = 4e6; |
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| 190 | Node2_Radio2_TxData = 0.45*exp(t*j*2*pi*f1)+0.45*exp(t*j*2*pi*f2); |
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| 191 | % Node2_Radio2_TxData = 0.45*sin(t*2*pi*f1)+0.45*exp(t*j*2*pi*f2); |
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| 192 | % Node2_Radio2_TxData = 0.45*cos(t*2*pi*f1)+0.45*exp(t*j*2*pi*f2); |
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| 193 | |
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| 194 | % 2. Plot the transmitted data fft and waveform |
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| 195 | |
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| 196 | % Compute and plot the fft of the transmitted signal centered at baseband |
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| 197 | % Computation of fft is based on the example in MATLAB's fft |
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| 198 | % documentation, see help fft for more information on MATLAB's fft function |
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| 199 | % Comppute fft |
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| 200 | L=length(Node2_Radio2_TxData); % Get length of transmitted vector |
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| 201 | NFFT = 2^nextpow2(L); % Next power of 2 from length of y |
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| 202 | Y = fftshift(fft(Node2_Radio2_TxData,NFFT)/L); % Compute fft |
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| 203 | Fs=40e6; % Sampling frequency is equal to 40e6 |
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| 204 | f = Fs/2*linspace(-1,1,NFFT); |
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| 205 | |
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| 206 | % Plot plot fft. |
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| 207 | figure |
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| 208 | plot(f/10^6,abs(Y)) |
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| 209 | title('Spectrum of transmitted signal in current carrier channel') |
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| 210 | xlabel('Frequency (MHz)') |
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| 211 | ylabel('Magnitude') |
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| 212 | xlim([-10, 10]) |
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| 213 | |
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| 214 | % Plot amplitude versus sample |
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| 215 | figure; |
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| 216 | subplot(2,2,1); |
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| 217 | plot(real(Node2_Radio2_TxData)); |
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| 218 | title('Tx Node 1 Radio 2 I'); |
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| 219 | xlabel('n (samples)'); ylabel('Amplitude'); |
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| 220 | axis([0 2^14 -1 1]); % Set axis ranges. |
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| 221 | |
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| 222 | subplot(2,2,2); |
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| 223 | plot(imag(Node2_Radio2_TxData)); |
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| 224 | title('Tx Node 1 Radio 2 Q'); |
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| 225 | xlabel('n (samples)'); ylabel('Amplitude'); |
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| 226 | axis([0 2^14 -1 1]); % Set axis ranges. |
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| 227 | |
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| 228 | subplot(2,2,3); |
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| 229 | plot([0:1:length(Node2_Radio2_TxData)-1]/40e6,real(Node2_Radio2_TxData)); |
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| 230 | title('Tx Node 1 Radio 2 I'); |
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| 231 | xlabel('time (s)'); ylabel('Amplitude'); |
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| 232 | axis([0 (length(Node2_Radio2_TxData)-1)/40e6 -1 1]); % Set axis ranges. |
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| 233 | |
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| 234 | subplot(2,2,4); |
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| 235 | plot([0:1:length(Node2_Radio2_TxData)-1]/40e6,imag(Node2_Radio2_TxData)); |
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| 236 | title('Tx Node 1 Radio 2 Q'); |
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| 237 | xlabel('time (s)'); ylabel('Amplitude'); |
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| 238 | axis([0 (length(Node2_Radio2_TxData)-1)/40e6 -1 1]); % Set axis ranges. |
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| 239 | |
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| 240 | % 3. Prepare WARP node for transmission |
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| 241 | % Download the samples to be transmitted |
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| 242 | warplab_writeSMWO(udp_node2, RADIO2_TXDATA, Node2_Radio2_TxData); |
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| 243 | |
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| 244 | % Enable transmitter radio path in radio 2 in node 2 (enable radio 2 in |
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| 245 | % node 2 as transmitter) |
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| 246 | warplab_sendCmd(udp_node2, RADIO2_TXEN, packetNum); |
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| 247 | |
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| 248 | % Enable transmission of Node2's radio 2 Tx buffer (enable transmission |
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| 249 | % of samples stored in radio 2 Tx Buffer in node 2) |
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| 250 | warplab_sendCmd(udp_node2, RADIO2TXBUFF_TXEN, packetNum); |
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| 251 | |
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| 252 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 253 | % Attendees code : |
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| 254 | % 1. Prepare the WARP node for reception (sensing the medium) and send trigger to |
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| 255 | % start reception (trigger is the SYNC packet) |
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| 256 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 257 | |
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| 258 | %-------------------------------------------------------------------------% |
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| 259 | % USER CODE HERE |
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| 260 | |
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| 261 | % Enable radio 2 in node 1 as receiver by sending the 'RADIO2_RXEN' command |
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| 262 | % to node 1 using the 'warplab_sendCmd' function. |
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| 263 | |
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| 264 | % The 'warplab_sendCmd' function has three arguments which are specified below: |
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| 265 | %(The arguments in the 'warplab_setRadioParameter' function do not use the quotes '') |
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| 266 | |
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| 267 | % 1. The first argument of the 'warplab_sendCmd' function identifies the |
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| 268 | % node to which the command will be sent to. The id or handle to node 1 is |
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| 269 | % 'udp_node1'. |
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| 270 | |
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| 271 | % 2. The second argument of the 'warplab_sendCmd' function identifies the |
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| 272 | % command that will be sent. |
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| 273 | |
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| 274 | % 3. The third argument of the 'warplab_sendCmd' command is a field that is |
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| 275 | % not used at the moment, it may be used in future versions of WARPLab to |
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| 276 | % keep track of packets. Use 'packetNum' as the third argument of the |
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| 277 | % 'warplab_sendCmd' function. |
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| 278 | |
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| 279 | warplab_sendCmd(udp_node1, RADIO2_RXEN, packetNum); |
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| 280 | %-------------------------------------------------------------------------% |
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| 281 | |
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| 282 | %-------------------------------------------------------------------------% |
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| 283 | % USER CODE HERE |
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| 284 | |
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| 285 | % Enable storage of samples in the receive buffer that is connected to |
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| 286 | % radio 2 in node 1 by sending the RADIO2RXBUFF_RXEN command to |
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| 287 | % node 1 using the 'warplab_sendCmd' function. |
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| 288 | |
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| 289 | % The 'warplab_sendCmd' function has been described above |
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| 290 | |
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| 291 | warplab_sendCmd(udp_node1, RADIO2RXBUFF_RXEN, packetNum); |
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| 292 | %-------------------------------------------------------------------------% |
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| 293 | |
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| 294 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 295 | % Instructors code |
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| 296 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 297 | % Prime transmitter state machine in node 2. Node 2 will be |
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| 298 | % waiting for the SYNC packet. Transmission from node 2 will be triggered |
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| 299 | % when node 2 receives the SYNC packet. |
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| 300 | warplab_sendCmd(udp_node2, TX_START, packetNum); |
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| 301 | |
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| 302 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 303 | % Attendees code |
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| 304 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 305 | |
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| 306 | % Prime receiver state machine in node 1. Node 1 will be waiting |
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| 307 | % for the SYNC packet. Capture at node 1 will be triggered when node 1 |
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| 308 | % receives the SYNC packet. |
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| 309 | warplab_sendCmd(udp_node1, RX_START, packetNum); |
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| 310 | |
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| 311 | % Send the SYNC packet |
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| 312 | warplab_sendSync(udp_Sync); |
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| 313 | |
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| 314 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 315 | % Attendees code: |
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| 316 | % 2. Read the received samples from the WARP node |
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| 317 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 318 | BufferSize = 2^14; |
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| 319 | |
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| 320 | %-------------------------------------------------------------------------% |
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| 321 | % USER CODE HERE |
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| 322 | |
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| 323 | % Read the received samples from the WARP node using the |
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| 324 | % 'warplab_readSMRO' function. Store the samples output by the warplab_readSMRO |
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| 325 | % function samples in a variable named 'Node1_Radio2_RawRxData'. |
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| 326 | |
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| 327 | % The arguments of the 'warplab_readSMRO' function are the following: |
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| 328 | |
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| 329 | % 1. The first argument of the 'warplab_readSMRO' function identifies the |
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| 330 | % node from which samples will be read. In this exercise there is only one |
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| 331 | % node and the id or handle to node 1 is 'udp_node1'. |
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| 332 | |
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| 333 | % 2. The second argument of the 'warplab_readSMRO' function identifies the |
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| 334 | % receive buffer from which samples will be read. For this exercise samples |
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| 335 | % were captured in node 1 radio 2, hence, samples must be read from radio 2 |
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| 336 | % Rx buffer, the id for this buffer is 'RADIO2_RXDATA'. |
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| 337 | |
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| 338 | % 3. The third argument of the 'warplab_readSMRO' function is the number of |
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| 339 | % samples to read; reading of samples always starts from address zero in |
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| 340 | % the receive buffer. For this exercise set the third argument of the 'warplab_readSMRO' |
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| 341 | % function equal to 'BufferSize' which has been defined in the code to be |
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| 342 | % equal to 2^14 which is the maximum number of samples that can be stored |
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| 343 | % in the receive buffer, hence you will read the entire receive buffer |
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| 344 | |
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| 345 | [Node1_Radio2_RawRxData] = warplab_readSMRO(udp_node1, RADIO2_RXDATA, BufferSize); |
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| 346 | %-------------------------------------------------------------------------% |
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| 347 | |
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| 348 | % Process the received samples to obtain meaningful data |
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| 349 | [Node1_Radio2_RxData,Node1_Radio2_RxOTR] = warplab_processRawRxData(Node1_Radio2_RawRxData); |
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| 350 | |
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| 351 | % Read stored RSSI data |
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| 352 | [Node1_Radio2_RawRSSIData] = warplab_readSMRO(udp_node1, RADIO2_RSSIDATA, ceil(BufferSize/8)); |
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| 353 | |
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| 354 | % Process Raw RSSI data to obtain meningful RSSI values |
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| 355 | [Node1_Radio2_RSSIData] = warplab_processRawRSSIData(Node1_Radio2_RawRSSIData); |
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| 356 | |
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| 357 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 358 | % Instructors code |
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| 359 | % 4. Disable te transmitter path |
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| 360 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 361 | |
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| 362 | % Set radio 2 Tx buffer in node 2 back to Tx disabled mode |
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| 363 | warplab_sendCmd(udp_node2, RADIO2TXBUFF_TXDIS, packetNum); |
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| 364 | |
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| 365 | % Disable the transmitter radio |
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| 366 | warplab_sendCmd(udp_node2, RADIO2_TXDIS, packetNum); |
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| 367 | |
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| 368 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 369 | % Attendees code: |
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| 370 | % 3. Reset and disable the WARP node |
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| 371 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 372 | %-------------------------------------------------------------------------% |
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| 373 | % USER CODE HERE |
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| 374 | |
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| 375 | % Set radio 2 in node 1 back to Rx disabled mode by sending the |
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| 376 | % 'RADIO2_RXDIS' command to node 1 using the 'warplab_sendCmd' function. |
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| 377 | |
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| 378 | % The 'warplab_sendCmd' function has been described above |
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| 379 | |
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| 380 | warplab_sendCmd(udp_node1, RADIO2_RXDIS, packetNum); |
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| 381 | %-------------------------------------------------------------------------% |
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| 382 | |
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| 383 | %-------------------------------------------------------------------------% |
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| 384 | % USER CODE HERE |
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| 385 | |
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| 386 | % Set storage of samples in the receive buffer that is connected to |
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| 387 | % radio 2 in node 1 back to disabled mode by sending the RADIO2RXBUFF_RXDIS |
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| 388 | % command to node 1 using the 'warplab_sendCmd' function. |
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| 389 | |
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| 390 | warplab_sendCmd(udp_node1, RADIO2RXBUFF_RXDIS, packetNum); |
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| 391 | %-------------------------------------------------------------------------% |
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| 392 | |
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| 393 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 394 | % Attendees code: |
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| 395 | % 4. Compute and plot the fft of the received data |
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| 396 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 397 | % Computation of fft is based on the example in MATLAB's fft |
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| 398 | % documentation, see help fft for more information on MATLAB's fft function |
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| 399 | |
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| 400 | % Compute and plot the fft of the received signal |
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| 401 | % Compute fft |
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| 402 | L=length(Node1_Radio2_RxData); % Get length of transmitted vector |
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| 403 | NFFT = 2^nextpow2(L); % Next power of 2 from length of y |
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| 404 | Y = fftshift(fft(Node1_Radio2_RxData,NFFT)/L); % Compute fft |
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| 405 | Fs=40e6; % Sampling frequency is equal to 40e6 |
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| 406 | f = Fs/2*linspace(0-1,1,NFFT); |
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| 407 | |
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| 408 | % Plot fft |
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| 409 | figure |
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| 410 | plot(f/10^6,abs(Y)) |
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| 411 | title('Spectrum of received signal in current carrier channel') |
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| 412 | xlabel('Frequency (MHz)') |
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| 413 | ylabel('Magnitude') |
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| 414 | xlim([-10 10]) |
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| 415 | |
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| 416 | |
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| 417 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 418 | % Attendees code: |
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| 419 | % 5. Plot the received waveform |
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| 420 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 421 | figure |
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| 422 | subplot(2,2,1); |
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| 423 | plot(real(Node1_Radio2_RxData)); |
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| 424 | title('Rx Node 2 Radio 2 I'); |
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| 425 | xlabel('n (samples)'); ylabel('Amplitude'); |
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| 426 | axis([0 2^14 -1 1]); % Set axis ranges. |
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| 427 | subplot(2,2,2); |
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| 428 | plot(imag(Node1_Radio2_RxData)); |
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| 429 | title('Rx Node 2 Radio 2 Q'); |
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| 430 | xlabel('n (samples)'); ylabel('Amplitude'); |
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| 431 | axis([0 2^14 -1 1]); % Set axis ranges. |
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| 432 | |
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| 433 | % Plot amplitude versus time |
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| 434 | subplot(2,2,3); |
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| 435 | plot([0:1:length(Node1_Radio2_RxData)-1]/40e6,real(Node1_Radio2_RxData)); |
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| 436 | title('Rx Node 2 Radio 2 I'); |
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| 437 | xlabel('time (s)'); ylabel('Amplitude'); |
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| 438 | axis([0 (length(Node1_Radio2_RxData)-1)/40e6 -1 1]); % Set axis ranges. |
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| 439 | subplot(2,2,4); |
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| 440 | plot([0:1:length(Node1_Radio2_RxData)-1]/40e6,imag(Node1_Radio2_RxData)); |
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| 441 | title('Rx Node 2 Radio 2 Q'); |
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| 442 | xlabel('time (s)'); ylabel('Amplitude'); |
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| 443 | axis([0 (length(Node1_Radio2_RxData)-1)/40e6 -1 1]); % Set axis ranges. |
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| 444 | |
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| 445 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 446 | % Attendees code: |
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| 447 | % 6. Compute the Received Signal Strength Indicator (RSSI in dBm) of the received signal |
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| 448 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 449 | % RSSI measurements were stored in 'Node1_Radio2_RSSIData' variable. |
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| 450 | % Average over all measurements of RSSI |
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| 451 | RSSI_Avg = mean(Node1_Radio2_RSSIData); |
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| 452 | |
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| 453 | % Convert RSSIAvg to dBm. |
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| 454 | % The conversion is based on the following radio and RSSI vaue specifications: |
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| 455 | % For high receiver gain (Node1_Radio2_RxGain_RF = 3), RSSI_Avg=0 is -100dBm; RSSI_Avg=1023 is -30dBm. |
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| 456 | % For medium receiver gain (Node1_Radio2_RxGain_RF = 2), RSSI_Avg=0 is -85dBm; RSSI_Avg=1023 is -15dBm. |
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| 457 | % For low receiver gain (Node1_Radio2_RxGain_RF = 1), RSSI_Avg=0 is -70dBm; RSSI_Avg=1023 is 0dBm. |
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| 458 | |
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| 459 | RSSI_dBm = (70/1023)*RSSI_Avg - 70 - (Node1_Radio2_RxGain_RF-1)*15; |
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| 460 | fprintf('\nRSSI dBm = %5.2f\n',RSSI_dBm) |
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| 461 | |
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| 462 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 463 | % 7. Close sockets |
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| 464 | %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 465 | pnet('closeall'); |
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