A total hardware based GPS/GLONASS receiver

The paper describes a new approach for designing navigational satellite receivers, which allows the processing of satellite signals by hardware only, without a need for any software processing, including the convolution of the Glonass satellite frequencies. On the basis of this approach a receiver was designed and manufactured, using ASIC technology - a highly specialized hardware digital satellite signal processor, which does not require software signal processing. The measured values of navigational parameters and the satellite message are fed from the ASIC output directly-to the navigational processor. The paper describes the general receiver architecture but also provides a detailed description of the following main receiver hardware units: . digital PLL; . DLL with carrier aided pseudorange measurement; . narrow space correlator. The paper demonstrates that these units function in accordance with optimal (or near optimal signal processing algorithms and have some advantages if compared with the existing traditional solutions. The major innovations obtained during this study are being patented. A maritime and a portable prototype receivers have already been developed on the basis of the ASIC mentioned above and undergo federal testing, which have already demonstrated the following: . improvement of major receiver parameters, including accuracy and interference rejection; . the developed GPS/GLONASS receiver offers has to the user the well known advantages of dual systems receivers, has less functional units (and IC units accordingly) than the classical single and dual-system receivers, which is believed to reduce production cost.