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diff --git a/host/docs/gpsdo.rst b/host/docs/gpsdo.rst deleted file mode 100644 index 8ffff8672..000000000 --- a/host/docs/gpsdo.rst +++ /dev/null @@ -1,87 +0,0 @@ -======================================================================== -UHD - Internal GPSDO Application Notes (USRP-N2x0/E1X0 Models) -======================================================================== - -.. contents:: Table of Contents - -This application note describes the use of integrated GPS-disciplined oscillators (GPSDOs) for -the USRP N-Series and E1xx. For information regarding the GPSDO that is compatible with -the USRP X-Series, please see: - -`USRP-X3x0 Internal GPSDO Device Manual <./gpsdo_x3x0.html>`_ - -======= - ------------------------------------------------------------------------- -Specifications ------------------------------------------------------------------------- -* **Receiver type**: 50 channel with WAAS, EGNOS, MSAS -* **10MHz ADEV**: 1e-11 over >24h -* **1PPS RMS jitter**: <50ns 1-sigma -* **Holdover**: <11us over 3h -* **Phase noise**: - - * **1Hz:** -80 dBc/Hz - * **10Hz:** -110 dBc/Hz - * **100Hz:** -135 dBc/Hz - * **1kHz:** -145 dBc/Hz - * **10kHz:** <-145 dBc/Hz - -**Antenna Types:** - -The GPSDO is capable of supplying a 3V for active GPS antennas or supporting passive antennas. - ------------------------------------------------------------------------- -Installation Instructions ------------------------------------------------------------------------- -Instructions for mounting the GPSDO kit onto your USRP device can be found here: -`http://www.ettus.com/content/files/gpsdo-kit_2.pdf <http://www.ettus.com/content/files/gpsdo-kit_2.pdf>`_ - -******************************************** -Post-installation Task (N-Series only) -******************************************** - -**Note:** The following instructions are only necessary for UHD 3.4.* and below. - -This is necessary if you require absolute GPS time in your application -or need to communicate with the GPSDO to obtain location, satellite info, etc. -If you only require 10 MHz and PPS signals for reference or MIMO use -(see the `Synchronization Application Notes <./sync.html>`_), -it is not necessary to perform this step. - -To configure the USRP to communicate with the GPSDO, use the -**usrp_burn_mb_eeprom** utility: - -:: - - cd <install-path>/lib/uhd/utils - ./usrp_burn_mb_eeprom --args=<optional device args> --key=gpsdo --val=internal - - -- restore original setting -- - ./usrp_burn_mb_eeprom --args=<optional device args> --key=gpsdo --val=none - ------------------------------------------------------------------------- -Using the GPSDO in Your Application ------------------------------------------------------------------------- -By default, if a GPSDO is detected at startup, the USRP will be configured -to use it as a frequency and time reference. The internal VITA timestamp -will be initialized to the GPS time, and the internal oscillator will be -phase-locked to the 10 MHz GPSDO reference. If the GPSDO is not locked to -satellites, the VITA time will not be initialized. - -GPS data is obtained through the **mboard_sensors** interface. To retrieve -the current GPS time, use the **gps_time** sensor: - -:: - - usrp->get_mboard_sensor("gps_time"); - -The returned value will be the current epoch time, in seconds since -January 1, 1970. This value is readily converted into human-readable -format using the **time.h** library in C, **boost::posix_time** in C++, etc. - -Other information can be fetched as well. You can query the lock status -with the **gps_locked** sensor, as well as obtain raw NMEA sentences using -the **gps_gprmc**, and **gps_gpgga** sensors. Location -information can be parsed out of the **gps_gpgga** sensor by using **gpsd** or -another NMEA parser. |