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1. Introduction
1.1 Overview
The GPS-NX01 Smart Receiver is an ultra low power GPS receiver based on the proven technology of the
NemeriX NJ1030A chipset. The positioning application meets strict needs such as car navigation, mapping,
surveying, security, agriculture and so on. Only a clear view of the sky and apower supply are needed. With its
ultra low power consumption, the smart receiver tracks up to 16 satellites at a time, re-acquires satellite signals in
1 second (average) and updates position data every second.
The GPS-NX01 can be used as a general purpose GPS receiver with NMEA-0183 output. However, its most
unique feature is the ability to transfer GPS data (time, date, latitude and longitude) to a wide variety of telescopes
that understandthe Meade LX200 Command Set or Celestron NexStar Communication Protocol.
1.2 Features
The GPS-NX01 provides a host of features that make it easy to use:
?Fast time-to-first-fix and ultra low power consumption
?High performance NemeriX chipset tracks up to 16 satellites in parallel
?Compact design with integrated antenna/receiver
?Rechargeable Lithium cell sustains internal clock and memory (recharges during normal operation)
?One full duplex serial port with selectable baud rates and NMEA messages
?Supports standard NMEA-0183, Meade LX200 and Celestron NexStar communication protocols
?Automatically detects telescope type (Meade, Celestron or none)
?Switches to standard NMEA output after 30 seconds if no telescope is detected
?LED power indicator blinks to indicate receiver status
?Switches to sleep mode (LED off) 20 minutes after the telescope accepts GPS data
?Automatic cold start with no user initialization required
1.3 Specifications
The GPS-NX01 technical specifications are listed below:
?Size: 47 x 39 x 16 mm (1.9" x 1.5" x 0.6")
?Weight: 70 g (2.5 oz)
?Tracks up to 16 satellites (-152 dBm sensitivity)
?Warm start in 38 seconds (50%), cold start in 45 seconds (50%)
?Position accuracy: 3 meters CEP (50%), 7m (90%)
?Velocity: 0.1 meters/second, without SA
?Time: +/-100 nanosecond synchronized to GPS time
?Altitude: 18,000 meters (60,000 feet) max
?Velocity: 515 meters / second (1000 knots) max
?Acceleration: 4 G, max
?Interface: RS-232 with 2 m (78") cable (PS/2 Female)
?Baud rate: 9600 (default), 4800, 19200, 38400
?NMEA-0183 Version 2.2 ASCII output: GPGGA, GPGSA, GPGSV, GPRMC, GPVTG, GPGLL, GPZDA
?Meade LX200 Command Set
?Celestron NexStar Communication Protocol (requires firmware version 2.3, 104.0 or 4.0+)
?Power: 3.6 to 5.5 V @ 35 ma (normal) or 16 ma (sleep mode)
?Backup power: 3V rechargeable lithium cell (350 hours)
?Operating temperature: -40 to +85°C (-40 to +185°F)
?Relative humidity: 5% to 90% non-condensing
