Question on trigger antenna and IQ sampling

Question

Hi all, im asking question about triggering my own antenna. there's few questions about it. 1. im using TI boostxl antenna array (3 antenna) , periodic table are as follow antenna_1 : 1100, antenna_2 : 1010 antenna_3 : 1001. 
 From my understanding i changed : static const uint8_t ant_patterns[] = {0xC,0xA,0x9};
/*static const uint8_t ant_patterns[] = { 0x2, 0x0, 0x5, 0x6, 0x1, 0x4,
 0xC, 0x9, 0xE, 0xD, 0x8, 0xA };*/ 
 im not sure if there are any setting that still need to be changed ,when changed to my antenna. pls help me out! 2. how to increase the number of IQ sample from 45 to 90 ?

PaKa · Accepted Answer

You changed the table that contains the antenna control signal, that is correct. You changed from a 12 antenna solution to a 3 antenna solution since you have only 3 entries in the table. 
 The reference antenna is the first antenna in the array and will be used during the reference period. This is described both in the Product Specification of the device as well as in the nWP036, I hope you have read through these for clarity. 
 When you run the default locator code it will generate 45 samples as output, these will be 
 Reference antenna: 8 values (in your case 0x09] 
 Antenna 1: 1 value (in your case 0x0A) 
 Antenna 2: 1 value (in your case 0x0C) 
 Antenna 1: 1 value (in your case 0x0A) 
 Antenna 2: 1 value (in your case 0x0C) 
 +++++ until you have 45 samples. 
 You use the data from the reference period to determine the frequency and the phase of the received signal. You then compare the phase of this reference signal with the phase of the measured signals to determine the phase shifts of the antenna 1 and antenna 2 signals. These phase shift values are then used to calculate the angle of the incoming signal. 
 You will have to write the code for these parts, they are not part of the SDK as they will be highly depending on the antenna you plan to use. If you change the antenna then you will have to change this code as well. 
 If you want to include the reference antenna in the loop that is measured then just add it to the table and it will be part of the output pattern. 
 {0x09, 0x0A, 0x0C} gives ref, ref, ref, ref, ref, ref, ref, ref, Ant 1, Ant 2, Ant 1, Ant 2, Ant 1+++++ 
 while 
 {0x09, 0x0A, 0x0C, 0x09} gives ref, ref, ref, ref, ref, ref, ref, ref, Ant 1, Ant 2, ref, Ant 1, Ant 2, ref, Ant 1+++++

Question on trigger antenna and IQ sampling

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