A Clark / Mbed 2 deprecated RF_ID

Log Test Code

Dependencies:   C12832 mbed

Fork of VoltageThreshold by A Clark

AntennaLog.cpp@3:9b47638100af, 2014-04-08 (annotated)

Committer:
ajclark2
Date:
Tue Apr 08 21:01:31 2014 +0000
Revision:
3:9b47638100af
Log Test

Who changed what in which revision?

UserRevisionLine numberNew contents of line
ajclark2 3:9b47638100af 1 #include "mbed.h"
ajclark2 3:9b47638100af 2 #define PI 3.1415
ajclark2 3:9b47638100af 3 #include "C12832.h"
ajclark2 3:9b47638100af 4
ajclark2 3:9b47638100af 5 LocalFileSystem local("local"); // Create the local filesystem under the name "local"
ajclark2 3:9b47638100af 6
ajclark2 3:9b47638100af 7 C12832 lcd(p5, p7, p6, p8, p11);
ajclark2 3:9b47638100af 8
ajclark2 3:9b47638100af 9 Timer t;
ajclark2 3:9b47638100af 10
ajclark2 3:9b47638100af 11 AnalogIn ain_v1(p19); // Input voltage from antenna
ajclark2 3:9b47638100af 12
ajclark2 3:9b47638100af 13 // Global variables declared
ajclark2 3:9b47638100af 14 float v1, m, b, p_in, Pt, Gt, Gr, Pr, f, c, r;
ajclark2 3:9b47638100af 15 float lv_r[250], lv_v1[250];
ajclark2 3:9b47638100af 16 int k;
ajclark2 3:9b47638100af 17
ajclark2 3:9b47638100af 18 int main()
ajclark2 3:9b47638100af 19 {
ajclark2 3:9b47638100af 20
ajclark2 3:9b47638100af 21 // Open logging file
ajclark2 3:9b47638100af 22 FILE *fp = fopen("/local/mBedOutp.m", "w");
ajclark2 3:9b47638100af 23
ajclark2 3:9b47638100af 24 //logging setup
ajclark2 3:9b47638100af 25 for(k=0;k<250;k++)
ajclark2 3:9b47638100af 26 {
ajclark2 3:9b47638100af 27 lv_r[k] = 0.0;
ajclark2 3:9b47638100af 28 lv_v1[k] = 0.0;
ajclark2 3:9b47638100af 29 }
ajclark2 3:9b47638100af 30 k = 0;
ajclark2 3:9b47638100af 31
ajclark2 3:9b47638100af 32 t.start();
ajclark2 3:9b47638100af 33 while(k<250)
ajclark2 3:9b47638100af 34 {
ajclark2 3:9b47638100af 35 // Voltage to Power calculations
ajclark2 3:9b47638100af 36 v1 = ain_v1*3.33; // ain_v1; // Comes from antenna (Can adjust manually for now) (3.3 is for scaling voltage properly... ask Feemster why this is necessary.
ajclark2 3:9b47638100af 37 b = 2.095; // (volts) Direct function generator measurement
ajclark2 3:9b47638100af 38 m = .0316; // volts/dBm (Calculated at 2000 MHz and 0 and -40 dBm)
ajclark2 3:9b47638100af 39 p_in = (v1-b)/m; // Derived from v = m*p+b (linear relationship of voltage and power)
ajclark2 3:9b47638100af 40
ajclark2 3:9b47638100af 41 // Range equation Terms
ajclark2 3:9b47638100af 42 Pt = .0398; //(watts or 1mW or 0 dBm) Power Transmitted. This is ~16 dBm (.0398 watts) for an iphone 5
ajclark2 3:9b47638100af 43 Gt = 1; // Unitless (1 for FG) Shouldn't both of these gains be 'directive' gains, not power gains
ajclark2 3:9b47638100af 44 Gr = .007; // (.007) (7 mW) How do we get this? 7 milliwatt?
ajclark2 3:9b47638100af 45 Pr = pow(10, ((p_in-30)/10)); // (watts)
ajclark2 3:9b47638100af 46
ajclark2 3:9b47638100af 47 // Free Space Loss Terms
ajclark2 3:9b47638100af 48 f = 2400000000; // (Hz) This will be constant for a phone... but what to put for the FG
ajclark2 3:9b47638100af 49 c = 300000000; // m/s
ajclark2 3:9b47638100af 50
ajclark2 3:9b47638100af 51 r = (c*(sqrt(Pt*Gt*Gr)/Pr))/(4*PI*f);
ajclark2 3:9b47638100af 52
ajclark2 3:9b47638100af 53 printf("\rRange (meters) = %.3f\n\r",r);
ajclark2 3:9b47638100af 54 //printf("Power (watts) = %.3f\n\r",Pr);
ajclark2 3:9b47638100af 55 printf("Voltage into mBed = %.4f\n\r",v1);
ajclark2 3:9b47638100af 56 //printf("%.4f\n\r",v1);
ajclark2 3:9b47638100af 57
ajclark2 3:9b47638100af 58 lcd.cls();
ajclark2 3:9b47638100af 59 lcd.locate(0,3);
ajclark2 3:9b47638100af 60 lcd.printf("Voltage (volts) = %.4f",v1);
ajclark2 3:9b47638100af 61
ajclark2 3:9b47638100af 62 lcd.locate(0,15);
ajclark2 3:9b47638100af 63 lcd.printf("Range (meters) = %.4f",r);
ajclark2 3:9b47638100af 64
ajclark2 3:9b47638100af 65 //LOG stuff
ajclark2 3:9b47638100af 66 if(k<250)
ajclark2 3:9b47638100af 67 { lv_r[k] = r;
ajclark2 3:9b47638100af 68 lv_v1[k] = v1;
ajclark2 3:9b47638100af 69 k++;
ajclark2 3:9b47638100af 70 }
ajclark2 3:9b47638100af 71
ajclark2 3:9b47638100af 72 } // End of while=======================================================
ajclark2 3:9b47638100af 73
ajclark2 3:9b47638100af 74 if(1)
ajclark2 3:9b47638100af 75 {
ajclark2 3:9b47638100af 76
ajclark2 3:9b47638100af 77 for(k=0;k<250;k++)
ajclark2 3:9b47638100af 78 { fprintf(fp,"lv.r(%d,1) = %.3f;\n",k+1,lv_r[k]);
ajclark2 3:9b47638100af 79 fprintf(fp,"lv.v1(%d,1) = %.4f;\n",k+1,lv_v1[k]);
ajclark2 3:9b47638100af 80 }
ajclark2 3:9b47638100af 81
ajclark2 3:9b47638100af 82 }// End of IF loop
ajclark2 3:9b47638100af 83
ajclark2 3:9b47638100af 84 fclose(fp);
ajclark2 3:9b47638100af 85 } // End of main loop=======================================================