diff options
Diffstat (limited to 'host/docs/gpsdo.rst')
| -rw-r--r-- | host/docs/gpsdo.rst | 27 |
1 files changed, 16 insertions, 11 deletions
diff --git a/host/docs/gpsdo.rst b/host/docs/gpsdo.rst index 3b718fc20..8ffff8672 100644 --- a/host/docs/gpsdo.rst +++ b/host/docs/gpsdo.rst @@ -4,8 +4,13 @@ UHD - Internal GPSDO Application Notes (USRP-N2x0/E1X0 Models) .. contents:: Table of Contents -This application note describes the use of integrated GPS-disciplined -oscillators with Ettus Research USRP devices. +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 @@ -16,11 +21,11 @@ Specifications * **Holdover**: <11us over 3h * **Phase noise**: - * **1Hz:** -80dBc/Hz - * **10Hz:** -110dBc/Hz - * **100Hz:** -135dBc/Hz - * **1kHz:** -145dBc/Hz - * **10kHz:** <-145dBc/Hz + * **1Hz:** -80 dBc/Hz + * **10Hz:** -110 dBc/Hz + * **100Hz:** -135 dBc/Hz + * **1kHz:** -145 dBc/Hz + * **10kHz:** <-145 dBc/Hz **Antenna Types:** @@ -29,7 +34,7 @@ The GPSDO is capable of supplying a 3V for active GPS antennas or supporting pas ------------------------------------------------------------------------ Installation Instructions ------------------------------------------------------------------------ -Installation instructions can be found here: +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>`_ ******************************************** @@ -40,7 +45,7 @@ Post-installation Task (N-Series only) 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 10MHz and PPS signals for reference or MIMO use +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. @@ -49,7 +54,7 @@ To configure the USRP to communicate with the GPSDO, use the :: - cd <install-path>/share/uhd/utils + cd <install-path>/lib/uhd/utils ./usrp_burn_mb_eeprom --args=<optional device args> --key=gpsdo --val=internal -- restore original setting -- @@ -61,7 +66,7 @@ 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 10MHz GPSDO reference. If the GPSDO is not locked to +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 |