Two-channel signal circuit of Beidou system

Abstract

The utility model discloses a dual-channel signal circuit of a Beidou system. The dual-channel signal circuit comprises an antenna matching network, a power amplifier, a filter and a positioning chip processor, the antenna matching network is connected with a two-in-one external antenna, and the two-in-one external antenna is used for jointly accessing a B1 signal and a B2 signal to a radio frequency input end of the antenna matching network; the input end of the power amplifier is connected with an antenna matching network, and the power amplifier U2 is used for performing gain amplification on accessed B1 and B2 signals; the filter is connected with the power amplifier and is used for filtering the signals B1 and B2 after gain amplification respectively; the high-level output end of the filter is connected with the B1 matching network; and the low-level output end of the filter is connected with the B2 matching network. And the positioning chip processor is respectively connected with the B1 matching network and the B2 matching network and is used for accessing a B1 signal and a B2 signal. According to the utility model, the overall equipment cost of the circuit can be reduced while the requirement of dual-channel signal input is met.

Description

Technical Field

[0001] The utility model belongs to the technical field of communication equipment, and in particular relates to a dual-channel signal circuit of a Beidou system. Background Art

[0002] The BeiDou Navigation Satellite System (BDS), also known as COMPASS, is a global satellite navigation system independently developed by China. Comprising a space segment, a ground segment, and a user segment, the BeiDou Navigation Satellite System provides high-precision, highly reliable positioning, navigation, and timing services to a wide range of users around the world, 24 / 7. It also features short message communication capabilities, giving it preliminary global navigation, positioning, and timing capabilities. Currently, the BeiDou Navigation Satellite System mostly uses a single-channel design, B1 and B2, which suffers from poor positioning accuracy and a limited number of satellites to search. The few BeiDou modules that utilize dual-channel signal inputs (B1 = 1561.098 MHz, B2 = 1207.14 MHz) require a dual LNA and dual SAW design (i.e., a signal amplifier and filter for each signal path), resulting in higher overall device costs. Therefore, developing a dual-channel signal circuit for the BeiDou system to overcome these existing challenges remains a research area for those skilled in the art. Utility Model Content

[0003] The purpose of the utility model is to provide a dual-channel signal circuit of the Beidou system, which can reduce the overall equipment cost of the circuit while meeting the dual-channel signal input.

[0004] The utility model discloses a dual-channel signal circuit of the Beidou system, which includes:

[0005] An antenna matching network, the antenna matching network being connected to a two-in-one external antenna, the two-in-one external antenna being used to connect the B1 signal and the B2 signal to a radio frequency input terminal of the antenna matching network;

[0006] A power amplifier, wherein an input end of the power amplifier is connected to the antenna matching network, and the power amplifier U2 is configured to perform gain amplification on the received B1 signal and the B2 signal;

[0007] a filter, wherein the input end of the filter is connected to the output end of the power amplifier and is used to filter the B1 signal and the B2 signal after gain amplification respectively; the high-level output end of the filter is connected to the B1 matching network and is used to output the filtered B1 signal to the B1 matching network; and the low-level output end of the filter is connected to the B2 matching network and is used to output the filtered B2 signal to the B2 matching network;

[0008] A positioning chip processor is connected to the B1 matching network and the B2 matching network respectively, and is used to access the B1 signal and the B2 signal.

[0009] This technical solution employs a separate antenna matching network design where the B1 and B2 signals enter the same power amplifier, achieving AGC signal gain amplification. This eliminates the need for an LNA signal amplifier. After amplification, the B1 and B2 signals enter the filter and, respectively, pass through the B1 and B2 matching networks before entering the positioning chip processor. This eliminates one SAW filter compared to existing technologies.

[0010] Preferably, the antenna matching network includes a capacitor C34 and an inductor L12; one end of the capacitor C34 is grounded, and the other end is connected to the two-in-one external antenna and one end of the inductor L12; the other end of the inductor L12 is connected to the power amplifier; the antenna matching network is configured such that the linear impedance portion of its Smith chart parameter S11 is greater than 45 ohms and less than 55 ohms, its Smith (R+jX)X reactance portion is required to be between 10pF and 10nH, its S11 standing wave ratio is less than 3, and its insertion loss parameter S21 line loss is less than 0.5dB. The inductance of the inductor L12 is 9.1nH.

[0011] By adopting this technical solution: based on the above-mentioned specific configuration of the antenna matching network, signal distortion and power attenuation of B1 and B2 before entering the LNA are prevented.

[0012] Preferably, the power amplifier is an MXDLN14TP low-noise amplifier. The power amplifier is configured such that the impedance linear portion of its return loss parameter S11 is greater than 45 ohms and less than 55 ohms, the exponential portion of its return loss parameter S11 is required to be close to zero, and the line loss of its insertion loss parameter S21 is less than 1 dB.

[0013] Preferably, the filter adopts a SAW filter SAWFD1G20AA0FDA, which is provided with pins 6 and 9. Pin 6 is a high-level output terminal for outputting a high-level signal. Pin 9 is a low-level output terminal for outputting a low-level signal. Pin 3 of the power amplifier is connected to one end of capacitor C36, and the other end of capacitor C36 is respectively connected to pin 1 (RF IN port) of the filter and one end of inductor L13, and the other end of inductor L13 is grounded.

[0014] Preferably, the B1 matching network includes capacitor C31, capacitor C4 and capacitor C3; one end of the capacitor C31 is connected to the high-level output end of the filter, and the other end is respectively connected to one end of the capacitor C4 and one end of the capacitor C3; the other end of the capacitor C4 is grounded; the other end of the capacitor C3 is connected to the positioning chip processor; the B2 matching network includes capacitor C32, capacitor C11 and inductor L3; one end of the capacitor C31 is connected to the low-level output end of the filter, and the other end is respectively connected to one end of the capacitor C11 and one end of the inductor L3; the other end of the capacitor C11 is grounded; the other end of the inductor L3 is connected to the positioning chip processor.

[0015] Among them, the capacitance of capacitor C31 is 100PF, the capacitance of capacitor C4 is 4.7PF, and the capacitance of capacitor C3 is 8.2PF. The capacitance of capacitor C32 is

[0016] Preferably, the positioning chip processor adopts the GK9701 chip.

[0017] Compared with the prior art, the present invention has achieved the following technical advancements:

[0018] First of all, the utility model can realize B1 and B2 dual-channel signal input, which is more than the traditional single-channel satellite search, thus providing a more stable working environment and higher positioning accuracy, and is suitable for use scenarios such as drones, car positioning, and high-voltage line inspection robots.

[0019] Secondly, the present invention can realize B1 and B2 dual-channel signal input based on the use of only a single LNA and a single SAW structure, thereby significantly reducing equipment costs.

[0020] Finally, the equipment of the present invention has a simple structure and is suitable for mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural diagram of the present utility model.

[0022] Figure 2 for Figure 1 A partial enlarged view of the antenna matching network and power amplifier.

[0023] Figure 3 for Figure 1 A partial enlarged view of the middle filter and the B1 and B2 matching networks.

[0024] Figure 4 for Figure 1 A partial enlarged view of the positioning chip processor.

[0025] In the figure, the corresponding reference numerals of the various components are as follows:

[0026] 100, antenna matching network; 200, power amplifier; 300, filter; 410, B1 matching network; 420, B2 matching network; 500, positioning chip processor. DETAILED DESCRIPTION

[0027] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different perspectives and applications without departing from the spirit of the present invention.

[0028] Example 1, please refer to Figure 1-4 :

[0029] A dual-channel signal circuit of the Beidou system includes: an antenna matching network 100, a power amplifier 200, a filter 300, and a positioning chip processor 500.

[0030] The antenna matching network 100 is connected to a two-in-one external antenna, and the two-in-one external antenna is used to connect the B1 signal and the B2 signal to the RF input end of the antenna matching network 100; the input end of the power amplifier 200 is connected to the antenna matching network 100, and the power amplifier 200U2 is configured to gain amplify the connected B1 signal and the B2 signal; the input end of the filter 300 is connected to the output end of the power amplifier 200, and is used to filter the gain-amplified B1 signal and the B2 signal respectively; the high-level output end of the filter 300 is connected to the B1 matching network 410, and is used to output the filtered B1 signal to the B1 matching network 410; the low-level output end of the filter 300 is connected to the B2 matching network 420, and is used to output the filtered B2 signal to the B2 matching network 420; the positioning chip processor 500 is connected to the B1 matching network 410 and the B2 matching network 420 respectively, and is used to connect the B1 signal and the B2 signal.

[0031] In this example: the antenna matching network 100 includes a capacitor C34 and an inductor L12; one end of the capacitor C34 is grounded, and the other end is connected to the two-in-one external antenna and one end of the inductor L12 respectively; the other end of the inductor L12 is connected to the power amplifier 200; the antenna matching network 100 is configured so that the impedance linear portion of its Smith chart parameter S11 is greater than 45 ohms and less than 55 ohms, its Smith (R+jX)X reactance portion is required to be between 10pF and 10nH, its S11 standing wave ratio is less than 3, and its insertion loss parameter S21 line loss is less than 0.5dB.

[0032] The power amplifier 200 uses an MXDLN14TP low-noise amplifier. The power amplifier 200 is configured such that the linear impedance portion of its return loss parameter S11 is greater than 45 ohms and less than 55 ohms, the exponential portion of its return loss parameter S11 is required to be close to zero, and the line loss of its insertion loss parameter S21 is less than 1 dB.

[0033] The filter 300 adopts a SAW filter 300SAWFD1G20AA0FDA, which is provided with pins 6 and 9. Among them, pin 6 is a high-level output terminal for outputting a high-level signal. Pin 9 is a low-level output terminal for outputting a low-level signal. Pin 3 of the power amplifier 200 is connected to one end of capacitor C36, and the other end of capacitor C36 is respectively connected to pin 1 (RF IN port) of the filter 300 and one end of inductor L13, and the other end of the inductor L13 is grounded.

[0034] The B1 matching network 410 includes a capacitor C31, a capacitor C4, and a capacitor C3; one end of the capacitor C31 is connected to the high-level output end of the filter 300, and the other end is connected to one end of the capacitor C4 and one end of the capacitor C3; the other end of the capacitor C4 is grounded; the other end of the capacitor C3 is connected to the positioning chip processor 500;

[0035] The B2 matching network 420 includes a capacitor C32, a capacitor C11 and an inductor L3; one end of the capacitor C31 is connected to the low-level output end of the filter 300, and the other end is respectively connected to one end of the capacitor C11 and one end of the inductor L3; the other end of the capacitor C11 is grounded; the other end of the inductor L3 is connected to the positioning chip processor 500.

[0036] The positioning chip processor 500 adopts the GK9701 chip.

[0037] During its operation, the B1 and B2 signals enter the same power amplifier through the separate design of the antenna matching network, and the AGC signal gain is amplified by the power amplifier, thereby saving one LNA signal amplifier. After amplification, the B1 and B2 signals enter the filter and then enter the positioning chip processor through the B1 matching network and the B2 matching network, respectively, thereby saving one SAW filter. Therefore, the utility model can achieve B1 and B2 dual-channel signal input based on only a single LNA and single SAW structure. Compared with the traditional single-channel satellite search, it has more, thus providing a more stable working environment and higher positioning accuracy, suitable for use in scenarios such as drones, vehicle positioning, and high-voltage line inspection robots.

[0038] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they will still fall within the scope of protection of the present invention.

Claims

1. A dual-channel signal circuit for the Beidou system, characterized in that: include: An antenna matching network, the antenna matching network being connected to a two-in-one external antenna, the two-in-one external antenna being used to connect the B1 signal and the B2 signal to a radio frequency input terminal of the antenna matching network; A power amplifier, wherein an input end of the power amplifier is connected to the antenna matching network, and the power amplifier U2 is configured to perform gain amplification on the received B1 signal and the B2 signal; a filter, wherein the input end of the filter is connected to the output end of the power amplifier and is used to filter the B1 signal and the B2 signal after gain amplification respectively; the high-level output end of the filter is connected to the B1 matching network and is used to output the filtered B1 signal to the B1 matching network; and the low-level output end of the filter is connected to the B2 matching network and is used to output the filtered B2 signal to the B2 matching network; A positioning chip processor is connected to the B1 matching network and the B2 matching network respectively, and is used to access the B1 signal and the B2 signal.

2. The dual-channel signal circuit according to claim 1, characterized in that: The antenna matching network includes a capacitor C34 and an inductor L12; one end of the capacitor C34 is grounded, and the other end is respectively connected to the two-in-one external antenna and one end of the inductor L12; the other end of the inductor L12 is connected to the power amplifier; the antenna matching network is configured so that the impedance linear part of its Smith chart parameter S11 is greater than 45 ohms and less than 55 ohms, its Smith (R+jX)X reactance part is required to be between 10pF and 10nH, its S11 standing wave ratio is less than 3, and its insertion loss parameter S21 line loss is less than 0.5dB.

3. The dual-channel signal circuit according to claim 2, characterized in that: The power amplifier adopts an MXDLN14TP low-noise amplifier; the power amplifier is configured so that the impedance linear part of its return loss parameter S11 is greater than 45 ohms and less than 55 ohms, the exponential part of its return loss parameter S11 is required to be close to zero, and the line loss of its insertion loss parameter S21 is less than 1 dB.

4. The dual-channel signal circuit according to claim 3, characterized in that: The filter adopts SAW filter SAWFD1G20AA0FDA.

5. The dual-channel signal circuit according to claim 4, characterized in that: The B1 matching network includes capacitor C31, capacitor C4 and capacitor C3; one end of the capacitor C31 is connected to the high-level output end of the filter, and the other end is connected to one end of the capacitor C4 and one end of the capacitor C3 respectively; the other end of the capacitor C4 is grounded; the other end of the capacitor C3 is connected to the positioning chip processor; The B2 matching network includes capacitor C32, capacitor C11 and inductor L3; one end of the capacitor C31 is connected to the low-level output end of the filter, and the other end is respectively connected to one end of the capacitor C11 and one end of the inductor L3; the other end of the capacitor C11 is grounded; the other end of the inductor L3 is connected to the positioning chip processor.

6. The dual-channel signal circuit according to claim 5, characterized in that: The positioning chip processor adopts GK9701 chip.

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