Аннотации:
A short overview of two low-cost modern GNSS modules allowing parallel obtaining of raw GNSS data at two frequencies for the GPS, GLONASS, Galileo, BeiDou is presented. These modules are appreciably cheaper than the professional GNSS devices available on the market. Using a Xiaomi Mi 8 android smartphone equipped with a dual-frequency GNSS module BCM47755 and an original GNSS receiver based on the u-blox ZED-F9P module raw GNSS data were recorded. For carrying out a comparison study the data obtained by the IGS KZN2 station equipped with the Trimble Alloy professional geodetic GNSS receiver and the Trimble TRM 59800 antenna were used as reference. Results of comparison analysis of technical characteristics of these modules for solving the problem of total electron content obtaining of the ionosphere by the measurements of two-frequency phase combinations at frequencies $\mathrm{L}1+\mathrm{L}2$ and $\mathrm{L}1+\mathrm{L}5$ are described in the paper.