Method for calibrating phase errors of global positioning system (GPS) signal source

A technology of GPS signal and phase error, which is applied in the field of simulating the generation of GPS signal sources, and can solve problems such as technical problems and technical solutions that have not been found

CN102590837BInactive Publication Date: 2014-01-08UNIV OF ELECTRONICS SCI & TECH OF CHINA
4 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Publication Date
2014-01-08
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention relates to the technical field of simulative generation of GPS signal source, in particular to a method for calibrating phase errors of a GPS signal source. The technical scheme of the method includes calculating a frequency control word of a floating point format by utilizing an input Doppler frequency parameter; subjecting the frequency control word to a fix-point process and calculating an overall error produced within a calibrating time internal; controlling phase accumulation by using the frequency control word after the fix-point process; if the calibrating time is reached, adding the overall error into the accumulation result, storing and outputting the final result, and storing and outputting the accumulation result directly otherwise; and if a parameter updated time interval is reached, recalculating the frequency control word of the floating point format according to the Doppler frequency at the moment and repeating the above steps, and proceeding phase accumulation otherwise. According to the technical scheme of the method for calibrating the phase errors of the GPS signal source, the high accuracy of floating point accomplishment and simplicity and low cost of fixed point accomplishment are balanced and combined, and the finite word-length effect in the fixed point accomplishment process can be calibrated simultaneously.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to the technical field of simulating and generating a GPS signal source, in particular to a method for correcting the phase error of the GPS signal source. Background technique

[0002] The GPS signal source can provide repeatable analog signals for various researches, simulations and tests in the field of satellite navigation, which is helpful for the advancement of research work. At the same time, in environments where it is not convenient to install antennas, such as remote mountainous areas and areas with harsh climates, the GPS signal source can also ensure the normal operation of the navigation terminal, greatly reducing the construction and maintenance costs of installing antennas.

[0003] In the process of simulating the generation of GPS signals by the GPS signal source, it is necessary to calculate the frequency control word of the intermediate frequency carrier, the frequency control word of the C / A code and the freque...

Examples

Embodiment Construction

[0040] The implementation manner of the technical solution of the present invention will be described in detail below.

[0041] Step 1: Initialization, specifically including: setting parameters, including GPS signal carrier frequency f T =1575.42MHz, C / A code rate f C =1.023MHz, navigation message code rate f D =50Hz, sampling frequency f s =16.384MHz, sampling interval T s = 1 / 16.384us, intermediate frequency f I =5.12MHz, the word length L of the digital platform W=32bit, the maximum tolerance value of the phase error caused by the three frequency control word errors is 8192, and the rounding method is used to realize the fixed point, that is, Max_ΔFCW=0.5, and the finite word length effect correction interval T obtained from this is e =1ms, the number of data points N in the calibration interval e =T e / T s =16384, in addition, set the parameter update interval T u = 2ms, N u =T u / T e =2.

[0042] Step 2: Calculate the frequency control word in floating point...