From 43eafdd484c523e321f5d97d7a6c7f95cf130b9a Mon Sep 17 00:00:00 2001 From: Carles Fernandez Date: Sat, 28 Sep 2019 00:26:50 +0200 Subject: [PATCH] Improve documentation --- src/algorithms/PVT/libs/rinex_printer.cc | 1 + src/algorithms/tracking/libs/lock_detectors.h | 36 ++++++++++--------- 2 files changed, 20 insertions(+), 17 deletions(-) diff --git a/src/algorithms/PVT/libs/rinex_printer.cc b/src/algorithms/PVT/libs/rinex_printer.cc index 520358f56..1a4b9dc49 100644 --- a/src/algorithms/PVT/libs/rinex_printer.cc +++ b/src/algorithms/PVT/libs/rinex_printer.cc @@ -12069,6 +12069,7 @@ double Rinex_Printer::get_leap_second(const Glonass_Gnav_Ephemeris& eph, const d return leap_second; } + void Rinex_Printer::set_pre_2009_file(bool pre_2009_file) { pre_2009_file_ = pre_2009_file; diff --git a/src/algorithms/tracking/libs/lock_detectors.h b/src/algorithms/tracking/libs/lock_detectors.h index 852ea4a6b..44982ad2c 100644 --- a/src/algorithms/tracking/libs/lock_detectors.h +++ b/src/algorithms/tracking/libs/lock_detectors.h @@ -54,19 +54,20 @@ /*! \brief cn0_svn_estimator is a Carrier-to-Noise (CN0) estimator * based on the Signal-to-Noise Variance (SNV) estimator * - * Signal-to-Noise (SNR) (\f$\rho\f$) estimator using the Signal-to-Noise Variance (SNV) estimator: + * Signal-to-Noise (SNR) (\f$ \rho \f$) estimator using the Signal-to-Noise Variance (SNV) estimator: * \f{equation} * \hat{\rho}=\frac{\hat{P}_s}{\hat{P}_n}=\frac{\hat{P}_s}{\hat{P}_{tot}-\hat{P}_s}, * \f} - * where \f$\hat{P}_s=\left(\frac{1}{N}\sum^{N-1}_{i=0}|Re(Pc(i))|\right)^2\f$ is the estimation of the signal power, - * \f$\hat{P}_{tot}=\frac{1}{N}\sum^{N-1}_{i=0}|Pc(i)|^2\f$ is the estimator of the total power, \f$|\cdot|\f$ is the absolute value, - * \f$Re(\cdot)\f$ stands for the real part of the value, and \f$Pc(i)\f$ is the prompt correlator output for the sample index i. + * where \f$ \hat{P}_s=\left(\frac{1}{N}\sum^{N-1}_{i=0}|Re(Pc(i))|\right)^2 \f$ is the estimation of the signal power, + * \f$ \hat{P}_{tot}=\frac{1}{N}\sum^{N-1}_{i=0}|Pc(i)|^2 \f$ is the estimator of the total power, \f$ |\cdot| \f$ is the absolute value, + * \f$ Re(\cdot) \f$ stands for the real part of the value, and \f$ Pc(i) \f$ is the prompt correlator output for the sample index i. * - * The SNR value is converted to CN0 [dB-Hz], taking to account the coherent integration time, using the following formula: + * The SNR value is converted to CN0 [dB-Hz], taking into account the coherent integration time, using the following formula: * \f{equation} * CN0_{dB}=10*log(\hat{\rho})-10*log(T_{int}), * \f} - * where \f$T_{int}\f$ is the coherent integration time, in seconds. + * where \f$ T_{int} \f$ is the coherent integration time, in seconds. + * * Ref: Marco Pini, Emanuela Falletti and Maurizio Fantino, "Performance * Evaluation of C/N0 Estimators using a Real Time GNSS Software Receiver," * IEEE 10th International Symposium on Spread Spectrum Techniques and @@ -76,21 +77,22 @@ float cn0_svn_estimator(const gr_complex* Prompt_buffer, int length, float coh_i /*! \brief cn0_mm_estimator is a Carrier-to-Noise (CN0) estimator - * based on the Moments Method (MM) + * based on the Second- and Fourth-Order Moments Method (M2M4) * - * Signal-to-Noise (SNR) (\f$\rho\f$) estimator using the Moments Method: + * Signal-to-Noise (SNR) (\f$ \rho \f$) estimator using the Moments Method: * \f{equation} - * \hat{\rho}=\frac{\hat{P}_s}{\hat{P}_n}=\frac{\sqrt{2*\hat{M}_2^2 - \hat{M}_4 }}{\hat{M}_2-\sqrt{2*\hat{M}_2^2 - \hat{M}_4 }}, + * \hat{\rho}=\frac{\sqrt{2 \hat{M}_2^2 - \hat{M}_4 }}{\hat{M}_2-\sqrt{2 \hat{M}_2^2 - \hat{M}_4 }}, * \f} - * where \f$\hat{P}_s=\left(\frac{1}{N}\sum^{N-1}_{i=0}|Re(Pc(i))|\right)^2\f$ is the estimation of the signal power, - * \f$ \hat{M}_2=\frac{1}{N}sum^{N-1}_{i=0}|Pc(i)|^2 \f$, \f$\hat{M}_4 = \frac{1}{N}sum^{N-1}_{i=0}|Pc(i)|^4 \f$, \f$|\cdot|\f$ is the absolute value, - * \f$Re(\cdot)\f$ stands for the real part of the value, and \f$Pc(i)\f$ is the prompt correlator output for the sample index i. + * where + * \f$ \hat{M}_2=\frac{1}{N}\sum^{K-1}_{k=0}|P[k]|^2 \f$, \f$ \hat{M}_4 = \frac{1}{K}\sum^{K-1}_{k=0}|P[k]|^4 \f$, \f$ |\cdot| \f$ is the absolute value, + * and \f$ P[k] \f$ is the prompt correlator output for the sample index k. * - * The SNR value is converted to CN0 [dB-Hz], taking to account the coherent integration time, using the following formula: + * The SNR value is converted to CN0 [dB-Hz] taking into account the coherent integration time, using the following formula: * \f{equation} * CN0_{dB}=10*log(\hat{\rho})-10*log(T_{int}), * \f} - * where \f$T_{int}\f$ is the coherent integration time, in seconds. + * where \f$ T_{int} \f$ is the coherent integration time, in seconds. + * * Ref: D. R. Pauluzzi, N. C. Beaulieu, "A comparison of SNR estimation * techniques for the AWGN channel," IEEE Trans. on Comm., vol. 48, * no. 10, pp. 1681–1691, Oct. 2000. @@ -104,9 +106,9 @@ float cn0_mm_estimator(const gr_complex* Prompt_buffer, int length, float coh_in * \f{equation} * C2\phi=\frac{NBD}{NBP}, * \f} - * where \f$NBD=(\sum^{N-1}_{i=0}|Im(Pc(i))|)^2+(\sum^{N-1}_{i=0}|Re(Pc(i))|)^2\f$, - * \f$NBP=\sum^{N-1}_{i=0}Im(Pc(i))^2-\sum^{N-1}_{i=0}Re(Pc(i))^2\f$, and - * \f$Pc(i)\f$ is the prompt correlator output for the sample index i. + * where \f$ NBD=(\sum^{N-1}_{i=0}|Im(Pc(i))|)^2+(\sum^{N-1}_{i=0}|Re(Pc(i))|)^2 \f$, + * \f$ NBP=\sum^{N-1}_{i=0}Im(Pc(i))^2-\sum^{N-1}_{i=0}Re(Pc(i))^2 \f$, and + * \f$ Pc(i) \f$ is the prompt correlator output for the sample index i. * Ref: Van Dierendonck, A.J. (1996), Global Positioning System: Theory and * Applications, * Volume I, Chapter 8: GPS Receivers, AJ Systems, Los Altos, CA 94024.