CN111208537B

CN111208537B - GNSS receiver and data transmission method thereof

Info

Publication number: CN111208537B
Application number: CN202010199464.5A
Authority: CN
Inventors: 金蕾; 田雨; 黄策; 温小华
Original assignee: Shanghai Jingrong Network Technology Co ltd
Current assignee: Suzhou Tianshuo Navigation Technology Co.,Ltd.
Priority date: 2020-03-20
Filing date: 2020-03-20
Publication date: 2021-02-23
Anticipated expiration: 2040-03-20
Also published as: CN111208537A

Abstract

The invention discloses a GNSS receiver and a data transmission method thereof, wherein the GNSS receiver of the GNSS receiver comprises a positioning board card, the positioning board card comprises a writing-in module, a detection module and a processing module, the positioning board card is provided with a built-in memory, and the writing-in module is used for writing positioning data into the built-in memory; the detection module is used for detecting whether the positioning board card is connected with an upper computer through a USB (universal serial bus) line or not, if so, the writing module is closed and the upper computer is informed to display a memory icon representing the built-in memory; the processing module is used for converting signals transmitted by the upper computer into SDIO interface signals and writing the converted SDIO interface signals into the built-in memory. The invention not only can conveniently manage the files on the internal memory of the GNSS high-precision board card, but also can be used as a serial port to configure the board card to generate required data, thereby further improving the accuracy of GNSS positioning.

Description

GNSS receiver and data transmission method thereof

Technical Field

The invention relates to a GNSS receiver and a data transmission method thereof.

Background

The satellite navigation positioning technology has basically replaced the ground-based radio navigation, the traditional geodetic survey and the astronomical survey navigation positioning technology at present, and promotes the brand new development of the field of geodetic survey and navigation positioning. Nowadays, the GNSS system is not only an infrastructure of national safety and economy, but also an important mark for embodying the status of modernized big countries and the national comprehensive strength. Due to the important significance in politics, economy, military and other aspects, the major military countries and the economic bodies in the world compete to develop independent and autonomous satellite navigation systems.

The gnss (global Navigation Satellite system) refers to four global Navigation positioning systems including the us GPS, russian GLONASS, Galileo in europe and Beidou in our country, and can provide uninterrupted and high-precision global Navigation signal resources for users, thereby realizing all-weather real-time positioning, speed measurement and time service functions. The GNSS is widely applied to various fields such as navigation, surveying and mapping, disaster monitoring and scientific research at present, and along with the continuous improvement and development of the GNSS technology, the GNSS receiver or the processing chip is expected to break through the limits of cost, power consumption, size and the like, and can be assembled on intelligent terminals such as various foundation air-based space bases and the like, so that the development of positioning technologies such as automatic driving, unmanned aerial vehicles and space vehicles can be greatly promoted. In these application scenarios, signals are often degraded due to the dynamics of users, the openness of signal propagation, and the complexity of the receiving environment, which seriously damages the service performance of the GNSS, such as availability, reliability, continuity, and the like.

The existing high-precision positioning board cards of various GNSS receivers generally use a single serial port (UART) line to input commands and output data, and then the data to be stored is put on an SD card, but the existence of an SD card slot can cause the area of the board card to be larger, in addition, the SD card has many brands and models, the quality is good, the SD card is frequently hung or read and write are failed, and the data cannot be stored.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the defects of inconvenient use, large volume and poor positioning accuracy of a GNSS receiver in the prior art, and provide the GNSS receiver and the data transmission method thereof which can simplify user operation and improve positioning accuracy.

The invention solves the technical problems through the following technical scheme:

the GNSS receiver is characterized by comprising a positioning board card, wherein the positioning board card comprises a writing module, a detection module and a processing module, the positioning board card is provided with a built-in memory,

the writing module is used for writing positioning data into the built-in memory;

the detection module is used for detecting whether the positioning board card is connected with an upper computer through a USB (universal serial bus) cable or not, if so, the writing module is closed and the upper computer is informed to display a memory icon representing the built-in memory;

and the processing module is used for converting the signal transmitted by the upper computer into an SDIO interface signal and writing the converted SDIO interface signal into the built-in memory.

The writing module, the detection module and the processing module are arranged on the positioning board card and are realized through a CPU and a DRAM.

Preferably, the GNSS receiver includes a receiving antenna, a radio frequency front end module, a baseband signal processing module, and a positioning solution module,

the radio frequency front end module is used for receiving GNSS signals transmitted by the receiving antenna and processing the GNSS signals to acquire digital intermediate frequency signals;

the baseband signal processing module is used for capturing and processing the digital intermediate frequency signal to obtain tracking data;

the positioning resolving module is used for acquiring positioning data according to the tracking data;

the writing module is used for writing the positioning data into the built-in memory.

Preferably, the baseband signal processing module comprises a correlator, a phase detector, a filter and an NCO,

the correlator is used for correlating the digital intermediate frequency signal and a recurrent carrier signal generated by the NCO so as to obtain correlation values of the same-direction branch and the orthogonal branch;

the phase discriminator is used for receiving the correlation value and outputting a tracking error of a carrier phase;

the filter is used for filtering and denoising the tracking error of the carrier phase and then transmitting the tracking error to the NCO;

and the NCO is used for updating a carrier phase estimation value according to the latest tracking error of the carrier phase and then transmitting the carrier phase estimation value to the positioning calculation module.

Preferably, the baseband signal processing module further comprises a reading module,

the processing module is used for converting Doppler frequency data transmitted by the upper computer into SDIO interface signals and writing the converted SDIO interface signals into the built-in memory;

the reading module is used for reading Doppler frequency data in an internal memory, acquiring a Doppler frequency estimated value and transmitting the Doppler frequency estimated value to the NCO;

and the NCO updates the carrier phase estimation value according to the Doppler frequency estimation value and the carrier phase.

Preferably, the GNSS receiver further includes a setup module,

the setting module is used for verifying the identity of the user after the detection module detects that the positioning board card is connected with the upper computer through a USB (universal serial bus) line and outputting a read-write mode option after the identity is legal;

and the GNSS receiver is used for closing the writing module when the reading and writing mode selected by the user is an upper computer editing mode.

The invention also provides a data transmission method of the GNSS receiver, which is characterized in that the GNSS receiver comprises a positioning board card, the positioning board card comprises a writing module, a detection module and a processing module, the positioning board card is provided with a built-in memory, and the data transmission method comprises the following steps:

the writing module writes positioning data into the built-in memory;

the detection module detects whether the positioning board card is connected with an upper computer through a USB (universal serial bus) line, if so, the writing module is closed and the upper computer is informed to display a memory icon representing the built-in memory;

and the processing module converts signals transmitted by the upper computer into SDIO interface signals and writes the converted SDIO interface signals into the built-in memory.

Preferably, the GNSS receiver includes a receiving antenna, a radio frequency front end module, a baseband signal processing module, and a positioning calculation module, and the data transmission method includes:

the radio frequency front-end module receives a GNSS signal transmitted by the receiving antenna and processes the GNSS signal to acquire a digital intermediate frequency signal;

the baseband signal processing module captures the digital intermediate frequency signal to obtain tracking data;

the positioning resolving module acquires positioning data according to the tracking data;

the writing module writes the positioning data to the built-in memory.

Preferably, the baseband signal processing module includes a correlator, a phase detector, a filter and an NCO, and the data transmission method includes:

the correlator correlates the digital intermediate frequency signal and a recurrent carrier signal generated by the NCO to obtain correlation values of the same-direction branch and the orthogonal branch;

the phase discriminator receives the correlation value and outputs a tracking error of a carrier phase;

the filter filters and reduces noise of the tracking error of the carrier phase and then transmits the noise to the NCO;

and the NCO updates the carrier phase estimation value according to the latest tracking error of the carrier phase, and then transmits the carrier phase estimation value to the positioning calculation module.

Preferably, the baseband signal processing module further includes a reading module, and the data transmission method includes:

the processing module converts Doppler frequency data transmitted by an upper computer into SDIO interface signals and writes the converted SDIO interface signals into the built-in memory;

the reading module reads Doppler frequency data in an internal memory, obtains a Doppler frequency estimated value and transmits the Doppler frequency estimated value to the NCO;

Preferably, the GNSS receiver further includes a setting module, and the data transmission method includes:

the setting module verifies the identity of the user after the detection module detects that the positioning board card is connected with the upper computer through a USB (universal serial bus) line, and outputs a read-write mode option after the identity is legal;

and the GNSS receiver closes the writing module when the read-write mode selected by the user is the upper computer editing mode.

On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.

The positive progress effects of the invention are as follows:

according to the invention, a user only needs to use one USB wire, so that the file on the internal memory of the GNSS high-precision board card can be conveniently managed, and the USB wire can also be used as a serial port to configure the board card to generate required data, thereby reducing the number of external matching cables, simplifying the operation of the user and realizing 'one-wire dual-purpose'.

In addition, the accuracy of GNSS positioning can be further improved by utilizing the data writing function of the virtual serial port.

Drawings

Fig. 1 is a flowchart of a data transmission method according to embodiment 1 of the present invention.

Fig. 2 is another flowchart of a data transmission method according to embodiment 1 of the present invention.

Fig. 3 is an excellent flowchart of the data transmission method according to embodiment 1 of the present invention.

Detailed Description

The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention.

Example 1

Referring to fig. 1 and fig. 2, the present embodiment provides a GNSS receiver, which includes a positioning board, where the positioning board includes a writing module, a detection module, and a processing module, and a built-in memory is disposed on the positioning board.

The embodiment can be realized by using embedded software codes, and by using the existing CDC (communication Device class) ACM (abstract Control model) and MSC (Mass Storage class) protocols of the USB and combining with a FAT32 file system, a USB Cable is used for connecting the GNSS high-precision positioning board card and the PC, so that a USB disk and a virtual serial port can be simultaneously displayed on the computer.

The data in the U disk is GNSS data written by the board card CPU to the embedded memory (EMMC), and a user can copy the GNSS data conveniently. The existing U disk is read and written on a computer, which is equivalent to one host and one device, the application involves that CPUs of a PC and a board card access files of a built-in EMMC memory, which is equivalent to two hosts and one device, so that the condition that only one party can write and the other party can read but cannot write at the same time is required to be ensured. The virtual serial port may be used to input commands to the board on a serial port tool such as a Secure CRT and then produce corresponding outputs.

Further, with the above structure, the present embodiment can improve the positioning progress, and the GNSS receiver includes a receiving antenna, a radio frequency front end module, a baseband signal processing module, and a positioning resolving module,

Specifically, the baseband signal processing module comprises a correlator, a phase detector, a filter and an NCO,

Specifically, the baseband signal processing module further comprises a reading module,

The estimated Doppler frequency value can be estimated by the position of the satellite at the current moment. The Doppler frequency estimated value and the carrier phase tracking result are utilized to enable the carrier signal tracking to be more accurate, and the obtained positioning to be more accurate.

The GNSS receiver further comprises a setup module,

Referring to fig. 1, with the GNSS receiver, the present embodiment further provides a data transmission method, including:

step 100, writing positioning data into the built-in memory by the writing module;

step 101, the detection module detects whether the positioning board card is connected with an upper computer through a USB (universal serial bus) cable, if so, step 102 is executed, and if not, step 100 is returned;

step 102, closing the writing module and informing the upper computer to display a memory icon representing the built-in memory;

and 103, converting the signal transmitted by the upper computer into an SDIO interface signal by the processing module, and writing the converted SDIO interface signal into the built-in memory.

Referring to fig. 2, step 100 includes:

1001, the radio frequency front end module receives a GNSS signal transmitted by the receiving antenna and processes the GNSS signal to acquire a digital intermediate frequency signal;

step 1002, the baseband signal processing module performs capture processing on the digital intermediate frequency signal to obtain tracking data;

step 1003, the positioning calculation module acquires positioning data according to the tracking data;

step 1004, the writing module writes the positioning data to the built-in memory.

Referring to fig. 3, step 1002 includes:

step 10021, the correlator correlates the digital intermediate frequency signal and a recurring carrier signal generated by the NCO to obtain correlation values of an in-phase branch and an orthogonal branch;

step 10022, the phase discriminator receives the correlation value and outputs a tracking error of the carrier phase;

step 10023, the filter filters and reduces noise of the tracking error of the carrier phase, and then transmits the tracking error to the NCO;

and step 10024, the NCO updates the carrier phase estimation value according to the latest tracking error of the carrier phase, and then transmits the carrier phase estimation value to the positioning calculation module.

Step 10024 comprises:

and the NCO updates the carrier phase estimation value according to the latest Doppler frequency estimation value and the latest carrier phase.

Further, the GNSS receiver further includes a setting module, and the data transmission method includes:

According to the embodiment, a user only needs to use one USB wire, so that not only can files on an internal memory of the GNSS high-precision board card be managed conveniently, but also the USB wire can be used as a serial port to configure the board card to generate required data, the number of external matching cables is reduced, the operation of the user is simplified, and the dual-purpose one-wire mode is realized.

While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that these are by way of example only, and that the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention, and these changes and modifications are within the scope of the invention.

Claims

1. A GNSS receiver is characterized by comprising a positioning board card, wherein the positioning board card comprises a writing module, a detection module and a processing module, the positioning board card is provided with a built-in memory,

the processing module is used for converting signals transmitted by the upper computer into SDIO interface signals and writing the converted SDIO interface signals into the built-in memory;

the GNSS receiver comprises a receiving antenna, a radio frequency front-end module, a baseband signal processing module and a positioning resolving module,

the writing module is used for writing the positioning data into the built-in memory;

the baseband signal processing module comprises a correlator, a phase discriminator, a filter and an NCO,

the correlator is used for correlating the digital intermediate frequency signal and a recurrent carrier signal generated by the NCO so as to obtain correlation values of an in-phase branch and a quadrature branch;

the NCO is used for updating a carrier phase estimation value according to the latest tracking error of the carrier phase and then transmitting the carrier phase estimation value to the positioning resolving module;

the baseband signal processing module further comprises a reading module,

2. The GNSS receiver of claim 1, characterized in that the GNSS receiver further comprises a setup module,

3. A data transmission method of a GNSS receiver is characterized in that the GNSS receiver comprises a positioning board card, the positioning board card comprises a writing module, a detection module and a processing module, a built-in memory is arranged on the positioning board card, and the data transmission method comprises the following steps:

the writing module writes positioning data into the built-in memory;

the processing module converts signals transmitted by the upper computer into SDIO interface signals and writes the converted SDIO interface signals into the built-in memory;

the GNSS receiver comprises a receiving antenna, a radio frequency front-end module, a baseband signal processing module and a positioning resolving module, and the data transmission method comprises the following steps:

the writing module writes the positioning data to the built-in memory;

the baseband signal processing module comprises a correlator, a phase detector, a filter and an NCO, and the data transmission method comprises the following steps:

the correlator correlates the digital intermediate frequency signal and a recurrent carrier signal generated by the NCO to obtain correlation values of an in-phase branch and a quadrature branch;

the NCO updates a carrier phase estimation value according to the latest tracking error of the carrier phase, and then transmits the carrier phase estimation value to the positioning resolving module;

the baseband signal processing module further comprises a reading module, and the data transmission method comprises the following steps:

4. The data transmission method according to claim 3, wherein the GNSS receiver further includes a setup module, the data transmission method comprising: