setting the data imput type in config file. All the internal receiver
signal chain can work in complex short for the first time. Speed
improvement using custom gnss-sdr volk kernels for cshort data input
types.
(around 5% faster).
This optimization is enabled at this time only in
Tracking_DLL_PLL_C_Aid. Sample config can be found in
gnss-sdr_Hybrid_byte_sim.conf
This implements a generic loop filter. Based on the analog PLL filters
from Kaplan and Hegarty, with a bilinear (Tustin's) transform from
s-plane to z-plane ( 1/s -> T/2 ( 1 + z^-1 )/( 1 - z^-1 ) )
Also added tests. Note the "truth" outputs
were derived from an Octave implementation of the loop filter and
Octave's builtin filter function
1) Carrier_rotate_and_EPL_volk
This is a very efficient VOLK based carrier wipeoff and
Early/Prompt/Late correlation. The carrier wipe off is done using the
VOLK rotator functions, which means there is no need to generate a local
replica sinusoid.
2) Carrier_rotate_and_VEPL_Volk
This adds Very Early/Early/Prompt/Late/Very Late correlation with the
VOLK rotator implementation of carrier wipe-off
Volk memory alignement for signal vectors was using a hardcoded 16 bytes
value. This parameter is machine-dependant and thus, in modern machines
caused memory exceptions if the parameter not match.
All posix_memalign functions are now replaced by the GNU Radio
volk_malloc(vector_size (bytes), volk_get_alignement());
volk_get_alignement() returns the number of bytes to align the memory
blocks in the current processor.
The memory bug showed up when the receiver is configured with higher
sample rates (>4 Msps!)
- Added a total elapsed run time counter in main: now it is possible to compare the post-processing time with the signal duration. The elapsed time is reported in STD::COUT when GNSS-SDR finish the main thread.
git-svn-id: https://svn.code.sf.net/p/gnss-sdr/code/trunk@156 64b25241-fba3-4117-9849-534c7e92360d
- The executable file and the default configuration file is now changed from "./install/mercurio" and "./conf/mercurio.conf" to "./install/gnss-sdr" and "./conf/gnss-sdr.conf", respectively.
- Configuration file structure changed to define in a single entry the internal sampling frequency (after the signal conditioner). NOTICE that this change affects the all the adapters (acquisition, tracking, telemetry_decoder, observables, and PVT). All the adapters are now modified to work with this feature.
- Moved several in-line GPS L1 CA parameters (a.k.a magic numbers..) to ./src/core/system_parameters/GPS_L1_CA.h definition file.
- Tracking blocks now uses DOUBLE values in their outputs.
- Observables and PVT now are separated. PVT and their associated libraries are moved to ./src/algorithms/PVT
- Temporarily disabled the RINEX output (I am working on that!)
- GNSS-SDR screen output now gives extended debug information of the receiver status and events. In the future, this output will be redirected to a log file.
- Bug fixes:
- FILE_SIGNAL_SOURCE now works correctly when the user configures GNSS-SDR to process the entire file.
- GPS_L1_CA_DLL_PLL now computes correctly the PRN start values.
- GPS_L1_CA_DLL_FLL_PLL now computes correctly the PRN start values.
- Several modifications in GPS_L1_CA_Telemetry_Decoder, GPS_L1_CA_Observables, and GPS_L1_CA_PVT modules to fix the GPS position computation.
- New features
- Tracking blocks perform a signal integrity check against NaN outliers before the correlation process.
- Tracking and PVT binary dump options are now documented and we provide MATLAB libraries and sample files to read it. Available in ./utils/matlab" and "./utils/matlab/libs"
- Observables output rate can be configured. This option enables the GPS L1 CA PVT computation at a maximum rate of 1ms.
- GPS_L1_CA_PVT now can perform a moving average Latitude, Longitude, and Altitude output for each of the Observables output. It is configurable using the configuration file.
- Added Google Earth compatible Keyhole Markup Language (KML) output writer class (./src/algorithms/PVT/libs/kml_printer.h and ./src/algorithms/PVT/libs/kml_printer.cc ). You can see the receiver position directly using Google Earth.
- We provide a master configuration file which includes an in-line documentation with all the new (and old) options. It can be found in ./conf/master.conf
git-svn-id: https://svn.code.sf.net/p/gnss-sdr/code/trunk@84 64b25241-fba3-4117-9849-534c7e92360d
New tracking libraries:
- tracking_discriminators: Library with a set of code tracking and carrier tracking discriminators that is used by the tracking algorithms. (fully documented, including math algorithms using doxygen!)
- tracking_2rd_DLL_filter: Class that implements 2 order DLL filter for code tracking loop.
- tracking_2rd_PLL_filter: Class that implements 2 order PLL filter for carrier tracking loop.
- tracking_FLL_PLL_filter: Class that implements hybrid FLL and PLL filter for tracking carrier loop.
- CN_estimators: Library with a set of Carrier to Noise estimators and lock detectors. (fully documented, including math algorithms using doxygen!)
Tracking:
- gps_l1_ca_dll_pll_tracking: The existing DLL + PLL tracking module, which is the K.Borre and D.Akos one, is now completely re-factored. Now uses the above described libraries.
- gps_l1_ca_dll_fll_pll_tracking: This is a brand new tracking module, which implements the FLL assisted PLL described in Kaplan (2nd edition). (also documentedwith references)
Configuration options:
- The following tracking parameters are added:
;######### TRACKING CONFIG ############
; Tracking.implementation=GPS_L1_CA_DLL_PLL_Tracking or GPS_L1_CA_DLL_FLL_PLL_Tracking
Tracking.implementation=GPS_L1_CA_DLL_FLL_PLL_Tracking
;PLL filter bandwidth in Hz.
Tracking.pll_bw_hz=50.0;
;DLL filter bandwidth in Hz.
Tracking.dll_bw_hz=2.0;
;FLL filter bandwidth in Hz.
Tracking.fll_bw_hz=50;
;filter order: choice between 2 or 3 at this moment, only for FLL assisted PLL
Tracking.order=2;
;Correlator space in chips units
Tracking.early_late_space_chips=0.5;
Other files have also been modified with minor changes to adapt to new modules or minor bug fixes.
git-svn-id: https://svn.code.sf.net/p/gnss-sdr/code/trunk@80 64b25241-fba3-4117-9849-534c7e92360d
