The Orion dual-frontend receiver is an extension of DLD/GSOC's GPS Orion-S/HD reciever for space and high-dynamics applications. Following a design of Stanford University, the receiver provides two separate L1 frontends driven by a common 10 MHz reference oscillator. The two frontends are connected to independent inputs of the GP2021 correlator chip and can individually be assigned to the 12 tracking channels by the receiver software. With two frontends, signals from two distinct antennas can be processed simulataneously, which opens a wide range of advanced GPS applications. As a further option, the receiver board supports the use of an external reference oscillator (e.g. OCXO) if a higher frequency stability is required than offered by the internal TCXO.
Like its smaller brother, the dual-frontend Orion employs an advanced receiver software supporting accurate tracking, navigation, and timing. Stable carrier tracking, even at high dyanmcis, is ensured by a 3rd order PLL with FLL assist and low-noise code tracking is provided by a carrier aided narrow-band DLL.
The dual-frontend receiver can support a variety of applications beyond those of a standard receiver:
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