GPS Software-Defined Receiver



Global positioning system (GPS) software-defined receivers (SDRs) offer many advantages over their hardware-based counterparts, such as flexibility, modularity, and upgradability. A typical GPS receiver is readily expressible as a block diagram, making a graphical approach a natural choice for implementing GPS SDRs. This work presents a real-time, graphical implementation of a GPS SDR, consisting of two modes: acquisition and tracking. The acquisition mode performs a two-dimensional fast Fourier transform (FFT)-based search over code offsets and Doppler frequencies. The carrier-aided code tracking mode consists of the following main building blocks: correlators, code and carrier phase detectors, code and carrier phase filters, code generator, and numerically-controlled oscillator. The presented GPS SDR provides an abstraction level that enables future research endeavors.

Related Publications

  1. A graphical approach to GPS software-defined receiver implementation
    Z. Kassas, J. Bhatti, and T. Humphreys
    IEEE Global Conference on Signal and Information Processing, Dec. 3-5, 2013, Austin, TX, pp. 1226-1229