OpenBTS: N210 Instalasi GPSDO Kit

Kit Berisi

1 GPSDO modul
1 Kabel Power (2 wire)
2 Kabel RS 232, 22cm (3 wire)
1 Kabel RS 232, 8cm (3 wire)
2 SMB right angle ke kabel SMA right angle
1 MMCX to SMA Bulkhead cable
2 Sekrup

Catatan: Lakukan sambungan dengan kondisi USRP power off.

GPSDO

Konektor:

A. RS-232 (Pins: 1. TX, 2. GND, 3. RX)
B. 1 PPS
C. 10 MHz Ref Clock
D. Power (Pins: 1. GND, 2. GND, 3. +6V)
E. GPS Antenna

Instruksi:

1. Buka daughterboard dari motherboard USRP.
2. Untuk N2XX: Ubah jumper J510 di motherboard dari 1-2 ke 2-3 untuk menswitch dari external ref clock 10MHz ke GPSDO 10MHz Ref Clock.
3. Sekrup modul GPSDO di tempat yang di sediakan. Sekrup dilakukan untuk menjaga agar tidak goyang dengan getaran.
4. Sambungkan kabel power GPSDO ke J509 (N2XX) di motherboard, dan ke konektor D di modul GPSDO.
5. Sambungkan SMB ke kabel SMA antara konektor B dan J506 (N2XX-PPS2).
6. Sambungkan SMB ke kabel SMA antara konektor C dan J5-7 (CLK REF2).
7. Dalam kit termasuk tiga kabel serial yang tidak dapat di tukar2 untuk digunakan di berbagai revisi / model USRP. Kabel 8cm untuk N2XX revisi 4 dan E1XX revisi 5 dan atasnya. Kabel 22cm dengan kabel hitam tersambung di tengah pin untuk USRP N2xx revisi 2 & 3.
8. USRP N2xx Rev 4 atau yang lebih tinggi: Temukan J312 di belakang motherboard dekat sambungan power GPSDO dan sambungkan ke dua ujung dari kabel 8cm ke dua ujungnya.

9. USRP N2xx Rev 4 or higher: Locate J312 on the back of the motherboard near the GPSDO power connector and connect either end of the 8cm long cable to it. Ettus Research LLC 1043 N Shoreline Blvd Suite 100 Mountain View, CA 94043 USA P

+1

- 650 - 967 - 2870 – F

+1

- 866 - 807 - 9801 – e ttus . com Rev. 1 . 9 – 10 October 201 2

10. USRP E1 xx Rev 4: Locate J86 next to the PPS SMA connector on the front of the motherboard. The serial cable connector that has the black wire (and a colored dot) on pin 1 has to be connected t o J86 ensuring that the black wire (pin 1) is connected to the GND pin of J86. 11. USRP E1xx Rev 5 or higher: Locate J86 on the back of the motherboard near the GPSDO power connector and connect either end of the 8cm long cable to it.

12. Connect the other end of the serial cable to connector A on the GPSDO module. Ensure the black wire is connected to pin 2, if not it is either the wrong cable or connected backwards. 13. Remove the washer and nut from the MMCX to SMA-Bulkhead cable. Connect it to connector E and then insert SMA-Bulkhead connector through the hole in the rear panel. T ighten nut to fasten in place. 14. Replace the daughterboard pushing all the cables underneath. Module Specifications 1 PPS Accuracy ± 50ns to UTC RMS (1 - Sigma) GPS Locked Holdover Stability < ± 11 μ s over 3 hour period at +25C 1 PPS Output (OCXO Flywheel Generated) 3.3VDC CMOS RS - 232 Control NMEA & SCPI - 99 Control Commands, Integrated into UHD GPS Frequency L1, C/A 1574MHz GPS Antenna Active (3V compatible) or Passive GPS Receiver 50 Channels, Mobile, WAAS, EGNOS, MSAS capable Sensitivity Acquisition - 144dBm, Tracking - 160dBm TTFF Cold Start: <45 sec, Warm Start: 1 sec, Hot Start: 1 sec ADEV 1E - 11 at 1s Warm Up Time / Stabilization Time <5 min at +25C to 1E - 08 Accuracy Supply Voltage (Vdd) 6VDC Power Consumption <1.8W Max, 1.35W Typical Operating Temperature 0C to +60C Storage Temperature - 45C to 85C Oscillator Specifications Frequency Output 10MHz 10MHz Retrace ± 2E - 08 a fter 1 h our at 25C Frequency Stability Over Temperature (Unlock Condition) ± 2.5E - 08 Warm Up Time < 1 min at +25C Phase Noise at 10MHz 1Hz - 80dBc/Hz 10Hz - 110dBc/Hz 100Hz - 135dBc/Hz 1kHz - 145dBc/Hz 10kHz < - 145dBc/Hz Note: If your USRP model or revision is missing, please check online for an updated version of this document at : https://www.ettus.com/product/details/GPSDO

Referensi

• https://www.ettus.com/content/files/gpsdo-kit_4.pdf
• http://www.jackson-labs.com/index.php/products/firefly_1a