USINGADAPTIVE FILTERS FOR GPS RECEIVERS

Use of Comb Filters in GPS L1 Receivers

Comb filters can be designed by replacing single delays in digital filters by multiple delays. These filters are " periodic " in the sense that their frequency response repeats itself at fixed intervals. They are thus well suited to a signal such as GPS L1 which has a spectrum made up of lines separated by the code repetition frequency of 1 kHz. In this paper we examine how periodic filters can...

A Novel Interference Rejection Method for GPS Receivers

This paper proposes a new method for rejecting the Continuous Wave Interferences (CWI) in the Global Positioning System (GPS) receivers. The proposed filter is made by cascading an adaptive Finite Impulse Response (FIR) filter and a Wavelet Packet Transform (WPT) based filter. Although adaptive FIR filters are easy to implement and have a linear phase, they create self-noise in the rejection of...

Infrared Filters for Cryogenic Receivers

Using Handheld GPS Receivers for Precise Positioning

In general handheld GPS receivers are used for absolute positioning or for relative positioning using DGPS-services or WAAS/EGNOS signals. The positioning is realized using code pseudo-ranges. Moreover it is well known that some of the handheld receivers use phase-smoothed code for positioning. This means that the phase signal is available and may be used for Precise Differential GPS (PDGPS) po...

Aquarius Firmware for UNSW Namuru GPS Receivers

UNSW is well known for its work in the development of FPGA based GPS receivers. However, a hardware platform without suitable firmware severely limits the application of that hardware and for the Namuru, the only available firmware has been the GPS Architect and the GPL-GPS. Unfortunately, both of these firmware suites have their limitations and it is for this reason that the Aquarius firmware ...