面向低成本GNSS接收机终端的周跳修复策略

Cycle Slip Repair Strategy of Low-cost GNSS Receivers

关键词:  低成本  GNSS  载波相位  周跳修复

Key words:  Low-cost  GNSS  Carrier phase  Cycle slip repair

摘要:

载波相位周跳是影响低成本GNSS接收机观测质量的主要因素之一。提出了一种面向低成本GNSS接收机终端的周跳修复策略，通过两种不同观测结果的联合检测以避免时钟和星历突变导致的误修复，并利用载噪比和多项式拟合误差检测载波观测中的无效观测，旨在提升低成本接收机在多径等复杂场景下载波相位观测的可用性。该策略仅使用了单频载波相位和载噪比信息，适用于各类低成本的接收设备。分别在开阔场景和多径场景下使用小米8手机和F9P接收机进行观测试验，结果表明，所有的有效载波相位观测得到了正确修复，仅约0.7%的无效观测被误修复，验证了所提策略的有效性。

Abstract:

Carrier phase cycle slip is one of the main factors affecting the observation quality of low-cost receivers. A cycle slip repair strategy for low-cost GNSS receivers is proposed in this paper, which aims to improve the availability of carrier phase observations for low-cost receivers in complex environment, such as multipath environment. A combined test of two different observations is used in the proposed strategy to avoid the mistake repair caused by the sudden change of clock and ephemeris. Carrier-to-noise ratio and RMS polynomial fitting error are used to detect invalid observations in the carrier observation. Only single-frequency carrier phase and carrier-to-noise ratio are needed in this strategy, so it is suitable for all kinds of low-cost receivers. Observation experiments are carried out with Mi 8 mobile phones and F9P receivers in open sky environment and multipath environment respectively. The results show that the proposed repair strategy can effectively repair cycle slips and detect most of the invalid observations at the same time. Only about 0.7% of invalid observations are mistaken as cycle slip and are repaired by mistake, which verifies the effectiveness of the proposed strategy.