GPS作為間接基準鑒定精確導航系統的新方法

摘 要:隨著技術進步，精確導航系統與GPS處于同一精度，傳統的直接比對法不再適用。為此，研究了一種新的間接法，以提高基準精度，滿足鑒定要求。間接法是利用GPS天線陣測得多個基準值，然后采用最小二乘法，解出基準位置的精確值。編出了試驗數據處理軟件，客觀準確地評估了精度性能。它已成功地用于某項精確導航系統的鑒定試飛中，對后續項目具有參考價值。關鍵詞:間接基準; 精確導航系統; 鑒定; 最小二乘法; 基線矢量

中圖分類號:TN96-34; P2284文獻標識碼:A

文章編號:1004-373X(2010)17-0017-03

New Method of Precise Navigation System Evaluation with GPS as Indirect Reference

XU Wu-jun1， QIU Fang-wen1， MA Jun-sheng2

(1.Chinese Flight Test Establishment， Xi’an 710089， China; 2.IT Center of Xi'an Yan'an Company， Xi’an 710065， China)

Abstract: With the technology made progress， the precise navigation system is in same accuracy as GPS， and the traditional direct comparison method is not applicable anymore. The indirect method which can improve the reference accuracy and meet the requirements of evaluation is proposed. The principle of the indirect method is: several reference values are measured with GPS antenna array， the precise value of the reference position is solved with least square method after the event. The experimental data processing software was programmed and then the accuracy performance was evaluated objectively and exactly. The indirect method has been applied successfully to a flight test for a precise navigation system in certain project and got some referential values beneficial to follow-up projects.Keywords: indirect reference; precise navigation system; evaluation method; least square method; baseline vector

0 引 言

導航系統傳統的鑒定方法為直接對比法，即用比被試設備精度更高的測量設備作為其試飛基準設備，測量出被試設備的精度[1]。一般來說，試飛基準設備的精度至少應為被試設備的三倍[2-3]，但是某些精確導航系統的精度太高[4]，無法找到適應其整個作用距離的基準設備。如果將差分GPS作為這類精確導航系統試飛的基準是不符合試飛鑒定要求的，因此精確導航系統飛行試驗，需要研究一種能以GPS作為間接基準，通過數學方法，精確解算出飛機基準位置，從而鑒定這類精確導航系統的精度。

1 方案概要[5-6]

精度通常用誤差表示，它包含系統誤差和隨機誤差[2-3]。為了減少隨機誤差的影響，可采用組合測量方法，進一步提高測量精度。組合測量是通過測量被測參數的組合量，然后對這些測量結果進行處理，求得被測參數的估計量。通常采用最小二乘法[7]，對組合測量數據進行計算。……