GPS (Global Positioning System) pseudo-random code tracking loop for preventing multi-path interference and method for preventing multi-path interference thereof

Abstract

The invention provides a GPS (Global Positioning System) pseudo-random code tracking loop for preventing multi-path interference and a method for preventing the multi-path interference thereof. The loop comprises a mixer, a correlator, an integration accumulator, a small wave phase detector, a loop filter and a local pseudo-random code generator. In the invention, the GPS pseudo-random code tracking loop adopts the small wave phase detector to detect a discontinuity point wherein the self-correlation function curve slope changes into a positive value from a zero value, is more accurate in the phase detection result, is free from the influence of the number of multi-path signals, and does not need to estimate the multi-path signals. In the invention, the pseudo code tracking accurate of the GPS pseudo-random code tracking loop is higher than the tracking accuracy of the typical sooner-later pseudo code delay locking loop so that the measurement accuracy of the pseudo range is improved; therefore, the invention is beneficial to positioning accurately.

Description

technical field [0001] The invention belongs to the field of radio navigation, and in particular relates to a GPS pseudo-random code tracking loop of multipath interference and an anti-multipath interference method thereof. Background technique [0002] The Global Positioning System (GPS) is based on radio navigation and has the characteristics of global, all-weather, continuity and real-time, and can provide users with services such as positioning, speed measurement and timing. The user receiver obtains the ranging signal of the broadband pseudo-random code transmitted by the satellite within the line-of-sight range, and then obtains the actual arrival time of the signal according to the accurate calculation of the local clock, thereby determining the distance to each satellite. The communication basis of the system is Spread spectrum communication. Each satellite uses a unique pseudo-random code, and the user receiver can distinguish a series of ranging signals received f...

AI Technical Summary

Problems solved by technology

However, its accuracy also depends on the selection of the filter order. A large filter order can certainly improve the estimation accuracy, but with the increase of the filter order, the convergence speed of the algorithm will also slow down, and when the received signal bandwidth is limited Even in the absence of multipath, large measurement errors will occur, so the application of this algorithm is limited in reality

Images