Please note the text and sub-pages below is for reference only as we officially ceased operations now.
Taking from the experience done with NSL Primo, we designed a simple USB dongle. The first version was on a two layer PCB (not optimal for RF, but so much cheaper to manufacture) to give the opportunity to people with smaller budgets to start experimenting with SDR GNSS. This new release of the dongle moves to a professional build, on 4 layers with controlled impedance and it's the best tool to start familiarising with GPS, Galileo, Glonass, and Beidou2.
We called it SdrNav00. Its main components are:
- Maxim/Dallas MAX2769 ('B' option possible) Universal GPS receiver
- Xilinx XC2C64A Coolrunner CPLD
- Cypress CY7C68013A USB High Speed MCU
For who is not familiar with the original NSL Primo, here is the main characteristics:
- captures a signal between 1550MHz and 1620MHz (high RNSS band)
- up to 18MHz bandwidth recording (useful for e.g. Galileo CBOC and Glonass) at 32Msps/4bit (2I + 2Q)
- fully reconfigurable glue logic to compress the stream thus reducing the data rate on the USB high-speed bus (useful for running SW receivers on embedded platforms with limited USB host capabilities)
- unlimited recording time
Note: The Windows and Linux codes are different! This applies to both FX2 and CPLD FW (which are not open source yet).
On Windows, SdrNav00 is transmits a binary stream with I&Q packed in two nibbles of the same byte using FS=16.368Msps and FIF=4.092MHz for an equivalent USB data rate of about 8MByte/sec.
On Linux, SdrNav00 is configured to output INT8 samples (real only) using FS=5.456Msps and FIF=4.092MHz for an equivalent USB data rate of about 5.5MByte/sec.
The reason behind the above difference is to provide the users with great sampling flexibility (Windows version) and the GPS-SDR software to work in an optimal way (Linux version).