A satellite navigation signal forwarding device suitable for anti-interference receiver

Abstract

The present invention discloses a satellite navigation signal forwarding device suitable for an anti-interference receiver, comprising: a receiving antenna array module, used to realize multiple antennas to receive satellite navigation signals simultaneously; a processing module, used to realize tracking, parameter extraction, coherent synthesis and forwarding synthesis of each satellite signal; a forwarding antenna module, used to realize forwarding output of the synthesized signal; the receiving antenna array module, the processing module and the forwarding antenna module are connected in sequence. The present invention uses multiple receiving antennas to receive satellite signals simultaneously, uses coherent synthesis technology to increase the power of satellite signals, improves the signal-to-noise ratio of satellite signals, and reduces the output power of the forwarding antenna, so that the forwarding signal power received by the anti-interference receiver is always lower than the noise power, ensuring that the anti-interference receiver can stably receive the forwarding signal.

Description

Technical Field

[0001] The present invention relates to the technical field of satellite navigation signal processing, and more specifically, to a satellite navigation signal forwarding device suitable for an anti-interference receiver. Background Art

[0002] In places where satellite navigation signals cannot be directly incident, signal repeaters are usually used to forward satellite signals to achieve receiver positioning. The satellite signal power received by the receiving antenna is around -133dBm, which is significantly lower than the noise power of -100dBm, so the satellite navigation signal is a weak signal. The working principle of a conventional signal repeater is that the receiving antenna is set up in an open area such as the roof, and after filtering, amplification and other processing, it is input into the room through a wired method, and then radiated to the receiving device through the repeater antenna. Usually, the power of the repeater signal received by the receiver is higher than the noise power, between -50dBm and -90dBm. Conventional signal repeaters are suitable for ordinary receivers, but for indoor antenna array anti-interference receivers, strong power signals will cause the receiver to mistake them for interference signals and completely suppress them, resulting in the receiver being unable to receive signals normally; by reducing the power of the repeater signal to below -100dBm, the signal-to-noise ratio of the received signal will be further reduced, and the anti-interference receiver will also be unable to stably receive signals.

[0003] The essential requirement for receiving interference receiver signals is that the total power of the received signal cannot be higher than the noise power, otherwise it will be strongly suppressed. At the same time, the signal-to-noise ratio of the satellite signal needs to meet certain sensitivity requirements to ensure stable reception of the satellite signal. Therefore, array synthesis technology can be introduced into the satellite navigation signal forwarding device, using multiple receiving antennas to simultaneously receive satellite signals, and simultaneously track the satellite signals of multiple antennas to obtain the phase information of each carrier, and then use coherent synthesis technology to increase the power of the satellite signal and improve the signal-to-noise ratio of the satellite signal; on this basis, reduce the output power of the forwarding antenna so that the signal power received by the receiver is always lower than the noise power, ensuring that the anti-interference receiver will not suppress the forwarded signal, and the anti-interference receiver can stably receive the signal. Therefore, a satellite navigation signal forwarding device suitable for anti-interference receivers can be developed. Summary of the invention

[0004] The object of the present invention is to provide a satellite navigation signal forwarding device suitable for an anti-interference receiver to overcome the defects of the prior art.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A satellite navigation signal forwarding device suitable for an anti-interference receiver, comprising:

[0007] A receiving antenna array module is used to enable multiple antennas to simultaneously receive satellite navigation signals;

[0008] Processing module, used to realize tracking, parameter extraction, coherent synthesis and forwarding synthesis of each satellite signal

[0009] A forwarding antenna module is used to realize the forwarding output of the synthesized signal;

[0010] The receiving antenna array module, the processing module and the forwarding antenna module are connected in sequence;

[0011] Further, the processing module includes M satellite tracking units, M satellite synthesis units and 1 forwarding synthesis unit, the satellite tracking unit, the satellite synthesis unit and the forwarding synthesis unit are connected in sequence, and M is the number of forwarded satellite signals;

[0012] The i-th satellite tracking unit simultaneously tracks the satellite i signal of N antennas and outputs the carrier phase difference of N satellite signals. :

[0013] ;

[0014] Where N is the number of array antennas, n is the antenna index, i is the satellite index, is the initial phase of the carrier of satellite i received by antenna n, assuming the first antenna is the reference antenna, The initial phase of the carrier wave of satellite i received by the reference antenna is used. The i-th satellite synthesis unit completes the coherent synthesis of the satellite i signal of N antennas. The coefficient of the coherent synthesis is :

[0015] ;

[0016] Where j is an imaginary number, and the coherent composite signal s output by the satellite synthesis unit is i (t) is:

[0017] ;

[0018] In the formula, r n (t) is the digital baseband signal output by the nth antenna, s i (t) is the coherent synthesis signal output by the synthesis unit, t is time, is the signal amplitude of satellite i, is the pseudo code of satellite i, is the carrier frequency of satellite i, the signal amplitude of the i-th satellite increases N times, and the noise power increases times, then the signal-to-noise ratio gain G of the satellite signal is: ;

[0019] Wherein, log10() is the logarithmic function with base 10;

[0020] The forwarding synthesis unit completes the forwarding synthesis of M coherent synthesis signals, and the output forwarding baseband signal p(t) is: ;

[0021] Where M is the number of forwarding satellites.

[0022] Furthermore, the receiving antenna array module completes the signal filtering, amplification, mixing and analog-to-digital conversion functions of multiple antennas, and then outputs the digital baseband array signals of multiple antennas. r n (t), its expression is:

[0023] ;

[0024] Where t is time, is the signal amplitude of satellite i, j is the imaginary sign, N is the number of array antennas, n is the antenna index, i is the satellite index, is the pseudo code of satellite i, is the carrier frequency of satellite i, is the initial phase of the carrier of satellite i received by antenna n, n(t) is Gaussian white noise, and exp() is an exponential function.

[0025] Furthermore, the forwarding antenna module completes the digital-to-analog conversion, up-conversion, amplification and output of the forwarding baseband signal p(t), and the forwarding antenna radiation power P t The calculation formula is as follows:

[0026] ;

[0027] Where P r is the received forwarded signal power of the anti-interference receiver, L loss is the path loss, G t is the gain of the forwarding antenna, G r The gain of the receiving antenna of the anti-interference receiver.

[0028] Compared with the prior art, the advantages of the present invention are: the present invention adopts multiple receiving antennas to simultaneously receive satellite signals, uses coherent synthesis technology to increase the power of satellite signals, improves the signal-to-noise ratio of satellite signals, and reduces the output power of the forwarding antenna at the same time, so that the forwarding signal power received by the anti-interference receiver is always lower than the noise power, ensuring that the anti-interference receiver can stably receive the forwarding signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 The present invention is a schematic diagram of a satellite navigation signal forwarding device applicable to an anti-interference receiver. DETAILED DESCRIPTION

[0031] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0032] See also Figure 1 As shown, this embodiment discloses a satellite navigation signal forwarding device suitable for an anti-interference receiver, including: a receiving antenna array module, used to enable multiple antennas to simultaneously receive satellite navigation signals; a processing module, used to achieve tracking, parameter extraction, coherent synthesis and forwarding synthesis of each satellite signal; a forwarding antenna module, used to achieve forwarding output of the synthesized signal; the receiving antenna array module, the processing module and the forwarding antenna module are connected in sequence.

[0033] In this embodiment, it is assumed that the B3I satellite signal of the Beidou system is forwarded, the carrier frequency of B3I is 1268.52MHz, the signal bandwidth is 10.23MHz, the satellite signal power input to the receiving array antenna is -130dBm, the Gaussian thermal noise power is -100dBm, the number of receiving antennas N=16, the number of forwarded satellites M=4, the radiation gain of the forwarding antenna Gt=3, the receiving antenna gain Gr of the anti-interference receiver is 0, and the anti-interference receiver can receive the signal when the signal-to-noise ratio SNR≥-30dB. Assume that the forwarding antenna is d=50m away from the anti-interference receiver, and it is required that the anti-interference receiver can normally receive the forwarded satellite signal within a range of more than 50m.

[0034] In this embodiment, the receiving antenna array module completes the signal filtering, amplification, mixing and analog-to-digital conversion functions of N antennas, and then outputs the digital baseband array signal r of N antennas. n (t), its expression is:

[0035] ;

[0036] Where t is time, is the signal amplitude of satellite i, j is the imaginary sign, N is the number of array antennas, n is the antenna index, i is the satellite index, is the pseudo code of satellite i, is the carrier frequency of satellite i, is the initial phase of the carrier of satellite i received by antenna n, n(t) is Gaussian white noise, and exp() is an exponential function.

[0037] In this embodiment, the processing module includes M satellite tracking units, M satellite synthesis units and 1 forwarding synthesis unit. The satellite tracking unit, satellite synthesis unit and forwarding synthesis unit are connected in sequence, and M is the number of forwarded satellite signals.

[0038] The i-th satellite tracking unit simultaneously tracks the satellite i signal of N antennas and outputs the carrier phase difference of N satellite signals. :

[0039] ;

[0040] Where N is the number of array antennas, n is the antenna index, i is the satellite index, is the initial phase of the carrier of satellite i received by antenna n, assuming the first antenna is the reference antenna, The initial phase of the carrier wave of satellite i received by the reference antenna is used. The i-th satellite synthesis unit completes the coherent synthesis of the satellite i signal of N antennas. The coefficient of the coherent synthesis is : ;

[0041] Where j is an imaginary number, and the coherent composite signal s output by the satellite synthesis unit is i (t) is:

[0042] ;

[0043] In the formula, r n (t) is the digital baseband signal output by the nth antenna, s i (t) is the coherent synthesis signal output by the synthesis unit, t is time, is the signal amplitude of satellite i, is the pseudo code of satellite i, is the carrier frequency of satellite i, the signal amplitude of the i-th satellite increases by N times, and the noise power increases times, then the signal-to-noise ratio gain G of the satellite signal is:

[0044] ;

[0045] Wherein, log10() is a logarithmic function with base 10. When N=16, G=12dB, which means that the signal-to-noise ratio of satellite i is improved by 12dB, which is equivalent to when the noise power is -100dBm, the satellite signal power is increased to -118dBm. Therefore, the satellite signal power is only 18dBm lower than the noise power.

[0046] In this embodiment, the forwarding synthesis unit completes the forwarding synthesis of M coherent synthesis signals, and outputs the forwarding baseband signal p(t) as: ;

[0047] Where M is the number of forwarding satellites.

[0048] In this embodiment, the forwarding antenna module completes the digital-to-analog conversion, up-conversion, amplification and output of the forwarding baseband signal p(t), and the forwarding antenna radiation power P t The calculation formula is as follows:

[0049] ;

[0050] Where P r The forwarding signal power received by the anti-interference receiver is usually -100dBm. loss is the path loss. When d=50m, L loss =68dB, G t is the gain of the forwarding antenna, G t =3, G r is the gain of the anti-interference receiver receiving antenna, G r =0, calculate the radiated power of the forwarding antenna P t =-34.55dBm.

[0051] Therefore, when d=50m, the received signal power P r =-100dBm, the satellite signal power is -118dBm, and the signal-to-noise ratio SNR is -18dB.

[0052] When d=100m, the received signal power P r =-106dBm, the satellite signal power is -124dBm, and the signal-to-noise ratio SNR is -24dB.

[0053] When d=200m, the received signal power P r =-112dBm, satellite signal power is -130dBm, and signal-to-noise ratio SNR is -30dB.

[0054] It can be seen that within the entire range of d=50m to 200m, the anti-interference receiver can be guaranteed to receive the forwarded satellite signals normally and stably.

[0055] The present invention adopts multiple receiving antennas to simultaneously receive satellite signals, uses coherent synthesis technology to increase the power of satellite signals, improves the signal-to-noise ratio of satellite signals, and reduces the output power of forwarding antennas at the same time, so that the power of forwarding signals received by the anti-interference receiver is always lower than the noise power, ensuring that the anti-interference receiver can stably receive forwarding signals.

[0056] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, various changes or modifications may be made within the scope of the appended claims. As long as they do not exceed the protection scope described in the claims of the present invention, they should be within the protection scope of the present invention.

Claims

1. A satellite navigation signal forwarding device suitable for an anti-interference receiver, characterized in that: include: A receiving antenna array module is used to enable multiple antennas to simultaneously receive satellite navigation signals; A processing module, used to realize tracking, parameter extraction, coherent synthesis and forwarding synthesis of each satellite signal; A forwarding antenna module is used to realize the forwarding output of the synthesized signal; The receiving antenna array module, the processing module and the forwarding antenna module are connected in sequence; The processing module includes M satellite tracking units, M satellite synthesis units and 1 forwarding synthesis unit, wherein the satellite tracking unit, the satellite synthesis unit and the forwarding synthesis unit are connected in sequence, and M is the number of forwarded satellite signals; The i-th satellite tracking unit simultaneously tracks the satellite i signal of N antennas and outputs the carrier phase difference of N satellite signals. : ; Where N is the number of array antennas, n is the antenna index, i is the satellite index, is the initial phase of the carrier of satellite i received by antenna n, assuming the first antenna is the reference antenna, The initial phase of the carrier wave of satellite i received by the reference antenna is used. The i-th satellite synthesis unit completes the coherent synthesis of the satellite i signal of N antennas. The coefficient of the coherent synthesis is : ; Where j is an imaginary number, and the coherent composite signal s output by the satellite synthesis unit is i (t) is: ； In the formula, r n (t) is the digital baseband signal output by the nth antenna, s i (t) is the coherent synthesis signal output by the synthesis unit, t is time, is the signal amplitude of satellite i, is the pseudo code of satellite i, is the carrier frequency of satellite i, the signal amplitude of the i-th satellite increases N times, and the noise power increases times, then the signal-to-noise ratio gain G of the satellite signal is: ; Wherein, log10() is the logarithmic function with base 10; The forwarding synthesis unit completes the forwarding synthesis of M coherent synthesis signals, and the output forwarding baseband signal p(t) is: ; Where M is the number of forwarding satellites.

2. The satellite navigation signal forwarding device suitable for an anti-interference receiver according to claim 1, characterized in that: The receiving antenna array module completes the signal filtering, amplification, mixing and analog-to-digital conversion functions of multiple antennas, and then outputs the digital baseband array signals of multiple antennas. r n (t), its expression is: ； Where t is time, is the signal amplitude of satellite i, j is the imaginary symbol, N is the number of array antennas, n is the antenna index, i is the satellite index, is the pseudo code of satellite i, is the carrier frequency of satellite i, is the initial phase of the carrier of satellite i received by antenna n, n(t) is Gaussian white noise, and exp() is an exponential function.

3. The satellite navigation signal forwarding device suitable for an anti-interference receiver according to claim 1, characterized in that: The forwarding antenna module completes the digital-to-analog conversion, up-conversion, amplification and output of the forwarding baseband signal p(t). P t The calculation formula is as follows: ; Where P r is the received forwarded signal power of the anti-interference receiver, L loss is the path loss, G t is the gain of the forwarding antenna, G r The gain of the receiving antenna of the anti-interference receiver.

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