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add open capacitance model (constant)

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TT 2016-10-19 07:18:41 +09:00
parent ab87c813a1
commit 520ebef659
3 changed files with 31 additions and 16 deletions
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2
dsp.c
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@ -135,7 +135,7 @@ void calclate_gamma(float *gamma)
}
rn = sqrtf(acc_ref / len) * 2e3 * len;
gamma[0] = -acc_r / rn;
gamma[1] = acc_i / rn;
gamma[1] = -acc_i / rn;
}
#endif

41
main.c
View file

@ -490,22 +490,32 @@ eterm_calc_es(void)
{
int i;
for (i = 0; i < 101; i++) {
// z=1/(jwc*z0) = 1/(2*pi*f*c*z0) Note: normalized with Z0
// s11ao = (z-1)/(z+1) = (1-1/z)/(1+1/z) = (1-jwcz0)/(1+jwcz0)
// prepare 1/s11ao for effeiciency
float c = 150e-15;
float z0 = 50;
float z = 6.2832 * frequencies[i] * c * z0;
float sq = 1 + z*z;
float s11aor = (1 - z*z) / sq;
float s11aoi = 2*z / sq;
// S11mo’= S11mo - Ed
// S11ms’= S11ms - Ed
float s11or = cal_data[CAL_OPEN][i][0] - cal_data[ETERM_ED][i][0];
float s11oi = cal_data[CAL_OPEN][i][1] - cal_data[ETERM_ED][i][1];
float s11sr = cal_data[CAL_SHORT][i][0] - cal_data[ETERM_ED][i][0];
float s11si = cal_data[CAL_SHORT][i][1] - cal_data[ETERM_ED][i][1];
// Es = (S11mo' + S11ms’)/(S11mo' - S11ms’)
float numr = s11or + s11sr;
float numi = s11oi + s11si;
// Es = (S11mo'/s11ao + S11ms’)/(S11mo' - S11ms’)
float numr = s11sr + s11or * s11aor - s11oi * s11aoi;
float numi = s11si + s11oi * s11aor + s11or * s11aoi;
float denomr = s11or - s11sr;
float denomi = s11oi - s11si;
float sq = denomr*denomr+denomi*denomi;
sq = denomr*denomr+denomi*denomi;
cal_data[ETERM_ES][i][0] = (numr*denomr + numi*denomi)/sq;
cal_data[ETERM_ES][i][1] = (numi*denomr - numr*denomi)/sq;
}
cal_status &= ~CALSTAT_SHORT;
cal_status &= ~CALSTAT_OPEN;
cal_status |= CALSTAT_ES;
}
@ -514,11 +524,16 @@ eterm_calc_er(int sign)
{
int i;
for (i = 0; i < 101; i++) {
// Er = sign*(1-Es)S11mo'
float s11or = cal_data[CAL_OPEN][i][0] - cal_data[ETERM_ED][i][0];
float s11oi = cal_data[CAL_OPEN][i][1] - cal_data[ETERM_ED][i][1];
float esr = 1 - cal_data[ETERM_ES][i][0];
float esi = -cal_data[ETERM_ES][i][1];
// Er = sign*(1-sign*Es)S11mo'
float s11or = cal_data[CAL_SHORT][i][0] - cal_data[ETERM_ED][i][0];
float s11oi = cal_data[CAL_SHORT][i][1] - cal_data[ETERM_ED][i][1];
float esr = cal_data[ETERM_ES][i][0];
float esi = cal_data[ETERM_ES][i][1];
if (sign > 0) {
esr = -esr;
esi = -esi;
}
esr = 1 + esr;
float err = esr * s11or - esi * s11oi;
float eri = esr * s11oi + esi * s11or;
if (sign < 0) {
@ -528,7 +543,7 @@ eterm_calc_er(int sign)
cal_data[ETERM_ER][i][0] = err;
cal_data[ETERM_ER][i][1] = eri;
}
cal_status &= ~CALSTAT_OPEN;
cal_status &= ~CALSTAT_SHORT;
cal_status |= CALSTAT_ER;
}
@ -622,12 +637,12 @@ static void cmd_cal(BaseSequentialStream *chp, int argc, char *argv[])
eterm_set(ETERM_ED, 0.0, 0.0);
if ((cal_status & CALSTAT_SHORT) && (cal_status & CALSTAT_OPEN)) {
eterm_calc_es();
eterm_calc_er(1);
eterm_calc_er(-1);
} else if (cal_status & CALSTAT_OPEN) {
eterm_copy(CAL_SHORT, CAL_OPEN);
eterm_set(ETERM_ES, 0.0, 0.0);
eterm_calc_er(1);
} else if (cal_status & CALSTAT_SHORT) {
eterm_copy(CAL_OPEN, CAL_SHORT);
eterm_set(ETERM_ES, 0.0, 0.0);
cal_status &= ~CALSTAT_SHORT;
eterm_calc_er(-1);

4
nanovna.h
View file

@ -85,8 +85,8 @@ extern trace_t trace[TRACES_MAX];
#define CALSTAT_APPLY (1<<8)
#define ETERM_ED 0 /* error term directivity */
#define ETERM_ER 1 /* error term refrection tracking */
#define ETERM_ES 2 /* error term source match */
#define ETERM_ES 1 /* error term source match */
#define ETERM_ER 2 /* error term refrection tracking */
#define ETERM_ET 3 /* error term transmission tracking */
#define ETERM_EX 4 /* error term isolation */