描述
Jackson Labs设计了Mini-JLTTM板以替换报废的Trimble公司的Mini-TTM GPSDO单元。2017年，JLT修改了主板以增加并发GNSS功能，如GPS、Galileo、Glonass、北斗、QZSS，并完全支持SBAS。该板的设计与Trimble单元兼容，但增加了各种功能，如1PPS外部输入、3轴板载加速度计、USB通信、内部天线电源、宽范围主电源、扩展的温度范围、较低的总高度（PCB高度，0.5英寸对0.8英寸），显著提高了热稳定性、Allan Deviation和相位噪声性能。还增加了对NMEA和SCPI通信命令的支持，并删除了对TSIP专有命令的支持。
特点
- 尺寸、安装和功能与Trimble Mini-T兼容
- 包括一个72信道并行GNSS接收机
- 扩展温度范围-40℃至+80℃
- USB和TTL串行通信
- 附加10MHz+13dBm输出端口
- TTL LOCK/EVENT#和GPS-FIX指示灯
技术参数
| Module Specification: | |||||
| 1 PPS Stability | <±10ns to UTC RMS (1-Sigma) GPS Locked (DOCXO) | ||||
| Serial Control | GPS NMEA and Status Output, SCPI-99 control, USB and TTL Port | ||||
| GPS Frequency, antenna power | C/A 1574MHz, 3.3V antenna-power built-in, 5V external supply option | ||||
| GPS Receiver | 72 Channels, GPS, Glonass, Galileo, BeiDou, QZSS, SBAS capable | ||||
| Sensitivity | Acquisition –148 dBm, Tracking -167 dBm (GPS & Glonass) | ||||
| GPS TTFF | Cold Start – <30 sec, Warm Start – 2 sec, Hot Start – 2 sec | ||||
| ADEV SOCXO | 1s < 7E-012, 1Ks < 7E-011, 10Ks < 8E-012 (25°C, no motion/airflow) | ||||
| ADEV DOCXO option | 1s < 5E-012, 1Ks < 3E-011, 10Ks < 3E-012 (25°C, no motion/airflow) | ||||
| Holdover at 25.0°C, no airflow, no motion/vibration, 5 days GPS locked | <5us in 5 hours (SOCXO), <4us in 24 hours (DOCXO) | ||||
| Warmup and Stabilization Time | <12 min at +25°C to <1E-09 Accuracy to GPS | ||||
| Supply Voltage (Vdd) | 5V ±1.0V | ||||
| Power Consumption | <2.4W (SOCXO), <3.2W (DOCXO) @25C, <8W during warmup | ||||
| Operating Temperature | -45°C to +80°C (SOCXO), 0°C to +75°C (DOCXO) | ||||
| 1PPS External Reference Input | Supports an optional external 1PPS input on pin 1 of power connector | ||||
| 10MHz outputs | 1x 10MHz at +5dBm, 1x optional 10MHz at +13dBm, ±3dB | ||||
| 3-axis accelerometer | Up to 20 readings/s, can be used for electronic g-compensation option | ||||
| Oscillator Specification (SOCXO): | |||||
| Frequency Output | 10MHz at +5dBm and +13dBm | ||||
| 10MHz Retrace | <±1E-09 After 1 Hour @ +25°C (no GPS) | ||||
| Frequency Stability over Temperature, and over 24hrs | ±6E-09 (SOCXO), ±0.5E-09 (DOCXO), <1E-012 over 24hrs (with GPS) | ||||
| Output Harmonics, spurs | <-50dBc/Hz, <-115dBc/Hz | ||||
| OCXO aging (fully compensated by GPS) | <±0.1ppm per year without GPS | ||||
| Phase Noise @ 10MHz | SOCXO | DOCXO | |||
| 1Hz | -90dBc/Hz | -94dBc/Hz | |||
| 10Hz | -128dBc/Hz | -132dBc/Hz | |||
| 100Hz | -148dBc/Hz | -142dBc/Hz | |||
| 1kHz | -153dBc/Hz | -150dBc/Hz | |||
| 10kHz | -155dBc/Hz | -152dBc/Hz | |||
| 100KHz | <-155dBc/Hz | -152dBc/Hz | |||
| Connections: | Connector Type: | ||||
| 2x 10MHz Sine Wave Out (second output not stuffed), GPS Antenna | SMA | ||||
| +5V Power, ext. 1PPS input, TTL serial port, Ant. power (3.3V to 5.5V) | Molex PN 70543-0005 | ||||
| USB Communication | Mini USB, USB 2.0 | ||||
