WO2020134855A1 - Système de communication par satellite - Google Patents

Système de communication par satellite Download PDF

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Publication number
WO2020134855A1
WO2020134855A1 PCT/CN2019/121951 CN2019121951W WO2020134855A1 WO 2020134855 A1 WO2020134855 A1 WO 2020134855A1 CN 2019121951 W CN2019121951 W CN 2019121951W WO 2020134855 A1 WO2020134855 A1 WO 2020134855A1
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Prior art keywords
signal
module
frequency
interference
modulation
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PCT/CN2019/121951
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English (en)
Chinese (zh)
Inventor
杨峰
任维佳
杜志贵
寇义民
Original Assignee
长沙天仪空间科技研究院有限公司
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Priority claimed from CN201811629492.5A external-priority patent/CN109698712B/zh
Priority claimed from CN201811629329.9A external-priority patent/CN109768823B/zh
Priority claimed from CN201910005961.4A external-priority patent/CN109802719B/zh
Application filed by 长沙天仪空间科技研究院有限公司 filed Critical 长沙天仪空间科技研究院有限公司
Priority to CN201980086573.1A priority Critical patent/CN113454919B/zh
Publication of WO2020134855A1 publication Critical patent/WO2020134855A1/fr

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/7097—Interference-related aspects
    • H04B1/71—Interference-related aspects the interference being narrowband interference
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/185—Space-based or airborne stations; Stations for satellite systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks

Definitions

  • the invention belongs to the technical field of wireless communication, and particularly relates to a satellite channel system.
  • OFDM Orthogonal Frequency Division Multiplexing
  • OFDM technology uses a discontinuous multi-tone modulation technology to combine a large number of signals in carriers of different frequencies into a single signal to complete signal transmission.
  • the development of OFDM technology is to improve the spectrum utilization rate of the carrier. Its characteristic is that each subcarrier is orthogonal to each other, so the spectrum after spread spectrum modulation can overlap each other, thus reducing the mutual interference between the subcarriers.
  • WiMAX communication system is a communication system based on OFDM modulation technology.
  • One of the important keys to using OFDM is to increase the ability to resist frequency selective fading, while also increasing the ability to resist narrowband interference.
  • the condition that the OFDM system can resist narrow-band interference is assuming that the power of the OFDM signal is much larger than that of the narrow-band interference; however, in practical applications, the transmission power of the OFDM signal is limited, so that when the external narrow-band interference signal is strong enough Normal demodulation performance will be deteriorated. Therefore, how to suppress narrow-band interference in limited spectrum resources is a problem that cannot be ignored.
  • Narrow-band strong interference is a common interference in practical applications, and its suppression can be done in the time domain or the frequency domain.
  • the time-domain method uses the correlation of narrow-band interference to perform adaptive filtering using the least mean square algorithm or the recursive least square algorithm.
  • the frequency domain method uses fast Fourier transform or inverse fast Fourier transform to zero the frequency of interference to eliminate interference.
  • the common frequency domain filtering mainly has the following two methods: The first method is a simple interference suppression technology based on FFT/IFFT, which outputs the data through windowing, FFT calculation, NBI filter processing and IFFT calculation, In the second way, in order to reduce the signal-to-noise ratio loss caused by windowing, an interference suppression technique based on superimposed fast Fourier transform is proposed.
  • the basic idea is to copy and shift the input data into windowing, get two windowed data together with the original windowed data, perform FFT transformation, and perform filtering in the frequency domain. After filtering, perform IFFT to obtain interference-free time-domain data. Align and merge the two data to get the final output.
  • the patent document with publication number CN105549035B discloses a device and method for detecting and eliminating narrowband interference in the frequency domain of a baseband signal.
  • the method includes: dividing an intermediate frequency signal into two channels, which are respectively output to a narrowband interference detector and a narrowband interference canceller.
  • the narrow-band interference detector performs interference detection on a received intermediate frequency signal to obtain interference detection information, and sends it to the narrow-band interference canceller, and the narrow-band interference canceller performs an operation on another received intermediate frequency according to the interference detection information.
  • the signal is processed for narrow-band interference cancellation.
  • the invention multiplies the time domain of the signal by a window function to perform windowing before performing the fast Fourier transform.
  • the multiplication in the time domain is equivalent to the convolution in the frequency domain, so the effect of windowing is only to reduce interference Sidelobes produced by the source.
  • the performance that windowing can improve depends on the frequency of the interference source. When the interference source is not located on a certain subcarrier frequency, spectrum leakage will occur, and narrowband interference will affect all adjacent subcarriers. And it does not consider the elimination of inter-carrier interference.
  • module as used herein describes any type of hardware, software, or combination of hardware and software that is capable of performing the function associated with the “module.”
  • the present invention provides a satellite communication system, especially a narrow-band multi-channel satellite communication system.
  • the signal can be transmitted to at least one narrow-band satellite via a ground station, and several ground stations can be based on each other Narrowband satellite relays are communicatively coupled.
  • the ground station includes at least an encoding module and a first modulation module.
  • the ground station is configured to modulate the signal as follows:
  • the encoding module is configured to The signal performs an encoding process to obtain an encoded signal;
  • the first modulation module is configured to perform a serial-to-parallel conversion process on the encoded signal to generate a first branch code stream and a second branch code stream, where: in the first When the branch code stream performs delay processing so that the first branch code stream and the second branch code stream are spaced apart from each other by a set symbol period, the first branch code stream sequentially performs the first The first-stage filtering process and the first-stage modulation process obtain the first modulation signal, and the second branch code stream performs the first-stage filtering process and the second-stage modulation process in sequence to obtain the second modulation signal; the first modulation The signal and the second modulation signal are jointly subjected to the second-stage modulation process to obtain a third modulation signal, wherein the third modulation signal is subjected to the second-stage filter process to complete the modulation process.
  • the first-stage filtering process is performed by a raised cosine roll-off filter
  • the second-stage filtering process is performed by a band-pass filter.
  • the signal spectrum will have a periodic extension phenomenon, which eventually generates inter-symbol interference, and there will be side-lobe interference within the frequency range of the modulated signal, which reduces the modulated signal.
  • the quality of the code increases the bit error rate.
  • the second-stage filtering process can reduce the size of side lobes in the frequency range to the specified decibel range, and can eliminate inter-symbol interference.
  • the third modulation signal generated by modulation has a lower average power ratio peak value than the prior art. And through the first-stage filtering process, any phase discontinuities of the first branch code stream and the second branch code stream can be effectively removed smoothly.
  • the encoding module is configured to perform encoding processing on the signal in the following manner: the BCH code generated by the signal through the BCH encoding process and the transmitted information frame together constitute several information subframes with set bits, the The information subframes are subjected to synchronous scrambling to sequentially perform RS encoding and convolutional encoding.
  • the convolutionally encoded data and the carrier synchronization bits, pilot sequence, unique code, and frame tail together form a complete modulated data frame, in which: When the bit length of the information subframe is less than the set bit length, it is complemented in a manner of supplementing zero codes.
  • the ground station further includes a filtering module, a second modulation module and a frequency conversion module, and the ground station further processes the signal in the following manner: the encoded signal is transmitted to the first modulation module at a set code rate After the modulation process is performed in, the first carrier frequency is transmitted to the filter module; the filter module is configured to perform a filter process on the signal it receives and transmit it to the second modulation module; the second modulation module uses the second The carrier frequency transmits the signal it receives to the frequency conversion module, wherein the frequency conversion module is configured to frequency convert the signal it receives to a set radio frequency output frequency.
  • the narrowband satellite includes at least a signal conditioning module and an interference cancellation module, and in the case where the signal is transmitted to the narrowband satellite via the ground station, the narrowband satellite is configured to perform on the signal as follows Processing:
  • the signal conditioning module is configured to: determine the frequency component of the signal and acquire several decomposed signals in different time-frequency spaces to separate the frequency content of the interference signal.
  • the interference cancellation module is configured to: align the frequency of the interference signal with the center of the subcarrier frequency of the communication channel and establish a first complex sinusoid, and obtain based on the multiplication processing of the first complex sinusoid and the signal to obtain Offset signals and introduce inter-carrier interference therefrom; sequentially performing windowing processing and fast Fourier transform processing on the offset signals to generate a frequency domain signal, which can eliminate the frequency by setting the subcarrier frequency to zero Interference signal to obtain an interference cancellation signal; in the case where the interference cancellation signal is processed by inverse fast Fourier transform to generate time-domain sampling samples, a second complex sine curve is established and according to the second complex sine curve and the time domain The sampling samples perform multiplication processing to eliminate the inter-carrier interference.
  • the signal conditioning module obtains the decomposed signal as follows: configure a filter bank with several different filtering levels, and each filtering level includes at least a low communication channel and a high communication channel, the low communication channel and Each of the high communication channels is configured with at least one set of discrete wavelet transformers, wherein: based on several filter levels of the filter bank, several subbands of different frequency bands will be acquired; The discrete wavelet transform process decomposes into several different time-frequency spaces.
  • the first complex sine curve is given by the formula Limited
  • the second complex sine curve is given by the formula Limited
  • the scrambling code period and polynomial of the synchronous scrambling process are 2 15 -1 and 1+X 14 +X 15 respectively ; where F s represents the sampling frequency and N is the number of fast Fourier transform sampling points .
  • the first-stage filtering process is performed by a first filter
  • the second-stage filtering process is performed by a second filter
  • the first filter is a raised cosine roll-off filter
  • the first The second filter is a band-pass filter
  • the first-stage modulation process is a quadrature modulation process
  • the second-stage modulation process is an in-phase modulation process.
  • the narrowband satellite further includes an interference detection module and a demodulation module
  • the interference detection module is configured to calculate an average power of the signal to determine whether there is an interference signal in the subband
  • the demodulation module is configured to interfere with the interference
  • the output signal of the elimination module is demodulated.
  • the interference cancellation module is further configured to obtain the frequency ⁇ f of the fast Fourier transform filter bank closest to the frequency of the interference signal, wherein: the frequency of the first complex sinusoid is ⁇ f, and the second complex The frequency of the sine curve is - ⁇ f.
  • the interference cancellation module can set the frequency of the fast Fourier transform filter bank corresponding to the subcarrier frequency to zero to set the frequency The interference signal is eliminated.
  • the present invention also provides a satellite communication system, especially a narrow-band satellite communication system, at least including a narrow-band satellite and a ground station, the narrow-band satellite is configured to at least suppress interference of the signal during signal relay Processing to realize the transmission of the signal between several ground stations, which converts the signal it receives to several different RF output frequencies to establish multi-channel transmission with the narrow-band satellites ,
  • the narrow-band satellite is configured to: respectively establish a first complex sinusoid and a second complex sinusoid, and determine the frequency component of the signal to separate the frequency content of the interference signal; based on the first complex sinusoid and
  • the first-stage multiplication processing of the signal acquires the first processed signal and introduces inter-carrier interference; eliminates the interference signal in a manner that the subcarrier frequency is set to zero to obtain the second processed signal; after the second processed signal is subjected to Fast Fourier In the case of inverse transform processing, the second-stage multiplication processing based on the second complex sinusoid and the second processed signal
  • the narrow-band satellite is further configured to: align the frequency of the interference signal with the frequency of the sub-carrier frequency of the communication channel; obtain the frequency ⁇ f of the fast Fourier transform filter bank closest to the frequency of the interference signal; The interference signal is eliminated by setting the frequency ⁇ f of the fast Fourier transform filter bank corresponding to the subcarrier frequency to zero.
  • the narrowband satellite is further configured to configure a filter bank with several different filtering levels, and each filtering level includes at least a low communication channel and a high communication channel, the low communication channel and the high communication channel
  • each filtering level includes at least a low communication channel and a high communication channel, the low communication channel and the high communication channel
  • Each is configured with at least one set of discrete wavelet transformers, wherein: several subbands of different frequency bands are obtained based on several filter levels of the filter bank; the signals contained in the subbands can be decomposed into several by discrete wavelet transform processing, respectively Different time-frequency space to separate the frequency content of the interference signal.
  • the ground station includes at least an encoding module, a first modulation module and a filtering module, the ground station is configured to process the signal it receives in the following manner: the encoding module performs at least BCH encoding processing, RS The encoding process and the convolutional encoding process perform a common processing on the signal to encode the signal to obtain an encoded signal; the first modulation module performs modulation processing on the encoded signal and transmits it to the filter module at a first carrier frequency, wherein : When acquiring the first tributary code stream and the second tributary code stream with a symbol period set apart from each other based on the encoded signal, at least based on the first tributary code stream and the second tributary code stream The tributary code stream obtains the first modulation signal and the second modulation signal respectively; the first modulation signal and the second modulation signal acquire the third satisfying the first carrier frequency in a manner of sequentially performing modulation processing and filtering processing Modulated signal.
  • the encoded signal acquires the first branch code stream and the second branch code stream in a manner of performing serial-parallel conversion processing, the first branch code stream or the second branch code
  • the streams can be set at intervals from each other in a manner to perform delay processing, wherein: in the case where the first branch code stream performs the delay processing, the first branch code stream performs the first
  • the first modulation signal is acquired in the manner of first-level filtering and second-stage modulation
  • the second branch code stream is acquired in the manner of sequentially performing the first-stage filtering and second-stage modulation A modulation signal
  • the first modulation signal and the second modulation signal acquire the third modulation signal in a manner of sequentially performing a second-stage modulation process and a second-stage filter process.
  • the first-stage filtering process is performed by a raised cosine roll-off filter
  • the second-stage filtering process is performed by a band-pass filter.
  • the signal spectrum will have a periodic extension phenomenon, which will eventually produce inter-symbol interference, and there will be side-lobe interference within the frequency range of the modulated signal, which reduces the modulated signal.
  • the quality of the code increases the bit error rate.
  • the second-stage filtering process can reduce the size of side lobes in the frequency range to the specified decibel range, and can eliminate inter-symbol interference.
  • the third modulation signal generated by modulation has a lower average power ratio peak value than the prior art. And through the first-stage filtering process, any phase discontinuities of the first branch code stream and the second branch code stream can be effectively removed smoothly.
  • the encoding process includes at least the following steps: the signal is subjected to the BCH encoding process to generate a BCH code, and the BCH code and the transmitted information frame together constitute a number of information subframes with set bits in the manner of supplementary zero codes;
  • the information subframe is sequentially subjected to synchronous scrambling processing, RS coding processing and convolutional coding processing to obtain processed data
  • the processed data is at least complete with the carrier synchronization bit, pilot sequence, unique code and frame tail Modulation data frame.
  • the ground station further includes a second modulation module and a frequency conversion module
  • the filter module includes at least a first filter and a second filter, wherein: the filter module controls the first One branch code stream and the second branch code stream perform the first-stage filtering process and the second filter performs the second-stage filtering process on the third modulated signal in a manner The signal is filtered; in the case where the third modulated signal is transmitted to the second modulation module through the filter module, the second modulation module transmits the signal it receives to the frequency conversion at the second carrier frequency Module; the frequency conversion module converts the signal it receives to a set radio frequency output frequency.
  • the present invention provides a satellite communication system based on suppression of narrow-band interference.
  • the narrow-band satellite and the ground station communicate with each other in a multi-channel manner to relay transmission of a combined signal having several constituent signals.
  • the narrowband satellite is configured to:
  • the second-stage multiplication processing based on the second complex sinusoid and the second processed signal eliminates the inter-carrier interference
  • the narrow-band satellite includes at least an interference detection module, a windowing module, a separation module and a regeneration module.
  • the narrow-band satellite is configured to Combined signal processing: the windowing module is configured to generate a window processing signal after limiting the frequency of the combined signal based on windowing processing; the interference detection module is configured to perform n-th power processing based on the window processing signal to Determining the modulation characteristic of at least one component signal and the symbol rate of its corresponding carrier; the separation module is configured to be based on the symbol rate when the window processed signal generates at least one continuous wave based on the nth power processing Resample the window processing signal by m times to generate a resampled signal, and use this to determine at least one symbol trajectory and at least one modulation type; the regeneration module is configured to pair based on the symbol trajectory and the modulation type The component signals are synthesized and reproduced to generate a synthesized signal.
  • the narrow-band satellite further includes a cancellation module and an inversion module, and in the case where the synthesized signal is determined to be an interference signal, the narrow-band satellite is configured to process the synthesized signal as follows:
  • the conversion module is configured to invert the synthesized signal to generate an inverted copy;
  • the cancellation module is configured to receive a copy of the combined signal and superimpose the inverted copy and the combined signal to Generate the first-level interference suppression signal.
  • the narrowband satellite further includes a signal preprocessing module and an interference cancellation module, the narrowband satellite is configured to process the first-level interference suppression signal in the following manner: the signal preprocessing module is configured to establish a A complex sinusoidal curve and a second complex sinusoidal curve, and determining the frequency component of the first-stage interference suppression signal to separate the frequency content of the interference signal.
  • the interference cancellation module is configured to: introduce inter-carrier interference in a manner of performing multiplication processing of the first interference suppression signal and the first complex sinusoidal curve to generate an offset signal; and obtain interference in a manner of setting a subcarrier frequency to zero Eliminating the signal and acquiring its time-domain sampling samples; eliminating the inter-carrier interference in a manner that the time-domain sampling samples and the second complex sinusoidal curve perform multiplication processing.
  • the interference cancellation module acquires the interference cancellation signal as follows: aligns the frequency of the interference signal with the frequency of the subcarrier frequency of the communication channel and acquires the fast Fourier transform filter closest to the frequency of the interference signal The frequency ⁇ f of the group; performing the windowing process and the fast Fourier transform process on the offset signal in sequence to generate a frequency domain signal; and setting the frequency ⁇ f of the fast Fourier transform filter bank corresponding to the subcarrier frequency to zero.
  • the signal preprocessing module is configured to configure a filter bank with several different filtering levels, and each filtering level includes at least a low communication channel and a high communication channel, the low communication channel and the high communication channel
  • Each channel is configured with at least one set of discrete wavelet transformers, wherein: based on several filter levels of the filter bank, several subbands of different frequency bands are obtained; signals contained in the subbands can be decomposed into discrete wavelet transforms to Several different time-frequency spaces.
  • the ground station includes at least an encoding module and a first modulation module, the ground station is configured to modulate the signal as follows: the encoding module is configured to perform encoding processing on the signal to obtain Coded signal; the first modulation module is configured to perform a serial-to-parallel conversion process on the coded signal to generate a first branch code stream and a second branch code stream, wherein: performing delay on the first branch code stream Processing such that when the first branch code stream and the second branch code stream are separated from each other by a set symbol period, the first branch code stream sequentially performs the first-stage filtering process and the first The first-level modulation process obtains a first modulation signal, and the second branch code stream sequentially performs the first-level filter process and the second-stage modulation process to obtain a second modulation signal; the first modulation signal and the second The modulated signals are collectively subjected to the second-stage modulation process to obtain a third modulated signal, wherein the third-modulated signal is subjected to the second-
  • the first-stage filtering process is performed by a raised cosine roll-off filter
  • the second-stage filtering process is performed by a band-pass filter.
  • the signal spectrum will have a periodic extension phenomenon, which will eventually produce inter-symbol interference, and there will be side-lobe interference within the frequency range of the modulated signal, which reduces the modulated signal.
  • the quality of the code increases the bit error rate.
  • the second-stage filtering process can reduce the size of side lobes in the frequency range to the specified decibel range, and can eliminate inter-symbol interference.
  • the third modulation signal generated by modulation has a lower average power ratio peak value than the prior art. And through the first-stage filtering process, any phase discontinuities of the first branch code stream and the second branch code stream can be effectively removed smoothly.
  • the encoding process includes at least the following steps: the signal undergoes BCH encoding processing to generate a BCH code, and the BCH code and the transmitted information frame together constitute a number of information subframes with set bits in a manner of supplementing zero codes;
  • the processed data at least together with the carrier synchronization bit, pilot sequence, unique code, and frame tail form a complete modulation Data Frame.
  • the ground station further includes a filtering module, a second modulation module and a frequency conversion module, and the ground station further processes the signal in the following manner: the encoded signal is transmitted to the first modulation module at a set code rate After the modulation process is performed in, the first carrier frequency is transmitted to the filter module; the filter module is configured to perform a filter process on the signal it receives and transmit it to the second modulation module; the second modulation module uses the second The carrier frequency transmits the signal it receives to the frequency conversion module, wherein the frequency conversion module is configured to frequency convert the signal it receives to a set radio frequency output frequency.
  • the narrowband satellite further includes a demodulation module
  • the interference detection module is configured to calculate the average power of the signal to determine whether there is an interference signal in the subband
  • the demodulation module is configured to output the interference cancellation module The signal is demodulated, where the frequency of the first complex sinusoid is ⁇ f and the frequency of the second complex sinusoid is - ⁇ f.
  • the filtering module performs the first-stage filtering process on the first branch code stream and the second branch code stream according to a first filter and a second filter on the third modulated signal Performing the second-stage filtering process by filtering the received signal; in the case where the third modulated signal is transmitted to the second modulation module through the filtering module, the second modulation module
  • the second carrier frequency transmits the signal it receives to the frequency conversion module;
  • the first filter is a raised cosine roll-off filter, the second filter is a band-pass filter;
  • the first-stage modulation processing is In quadrature modulation processing, the second-stage modulation processing is in-phase modulation processing.
  • each narrow-band interference signal when each narrow-band interference signal is aligned with the center of the sub-carrier frequency of the communication channel, it will cause inter-carrier interference.
  • the signal will no longer carry the narrow-band interference after the sub-carrier frequency aligned with the narrow-band interference is removed, and then the inter-carrier interference is removed from the signal. Therefore, before decoding, the signal removes all narrow-band interference and any potential side lobes, thereby eliminating spectral leakage.
  • the digital shaping filter of the present invention can eliminate inter-symbol interference, and thus can meet the Nyquist characteristic without inter-symbol interference, and can also smooth the waveform, and thus can accelerate the out-of-band attenuation speed of the modulated signal and improve the spectrum utilization rate.
  • the processing of the band-pass filter can make the modulation envelope smoother.
  • the present invention can receive signals with overlapping frequencies, detect and filter the interference signals contained therein, and can effectively improve the utilization rate of spectrum resources.
  • FIG. 1 is a schematic diagram of the modular connection relationship of the preferred narrowband multi-channel satellite communication system of the present invention
  • FIG. 2 is a schematic diagram of the modular structure of the preferred ground station of the present invention.
  • FIG. 3 is a schematic diagram of the modulation processing flow of the first modulation module preferred in the present invention.
  • FIG. 4 is a schematic diagram of the modular structure of the preferred narrowband satellite of the present invention.
  • FIG. 5 is a schematic diagram of the processing flow of the preferred interference cancellation module of the present invention.
  • FIG. 6 is a block diagram of a preferred RS code encoding of the present invention.
  • FIG. 7 is a coding block diagram of a preferred convolutional code of the present invention.
  • FIG. 8 is a schematic diagram of the processing flow of the preferred encoding module of the present invention.
  • FIG. 9 is a schematic diagram of a modular structure of another narrow-band satellite preferred by the present invention.
  • FIG. 10 is a schematic diagram of the processing flow of the combined signal of the narrowband satellite of the present invention. .
  • Narrow-band satellites 2 Ground station
  • interference detection module 101 interference detection module 102: interference cancellation module 103: demodulation module
  • signal conditioning module 105 analog-to-digital conversion module
  • 106 windowing module
  • coding module 202 first modulation module 203: filter module
  • first filter 203b second filter
  • first modulator 202b second modulator 202c: third modulator
  • Each "module” in the present invention may be one or more of a dedicated integrated chip, a server, and a server group.
  • the module of the present invention describes any kind of hardware, software, or combination of hardware and software that can perform the function associated with the “module”.
  • the present invention provides a multi-channel satellite communication system, which includes at least one narrow-band satellite 1 and several ground stations 2 that communicate with each other.
  • the multi-channel satellite communication system includes a narrow-band satellite 1, a first ground station 2a, and a second ground station 2b.
  • the first ground station 2a may send the data signal it receives to the narrowband satellite 1, and then relay it to the second ground station 2b through the narrowband satellite 1.
  • the second ground station 2b may also relay the data signal it receives to the first ground station 2a through the narrowband satellite 1.
  • the first ground station 2a and the second ground station 2b may individually have their respective gateways, and all the gateways may be communicatively coupled to each other through a common network.
  • the ground station 2 includes at least an encoding module 201, a first modulation module 202, a filtering module 203, a second modulation module 204, and a frequency conversion module 205.
  • the encoding module 201 is used to encode the original data information received by the ground station 2 and transmit the encoded digital signal to the first modulation module 202 according to the set code rate.
  • the first modulation module 202 is used to modulate the digital signal to be converted to the set first carrier frequency.
  • the digital signal modulated by the first modulation module 202 is transmitted to the filtering module 203 for filtering.
  • the digital signal filtered by the encoding module 201 of the filtering module 203 is transmitted to the second modulation module 204 for re-modulation to switch to the set second carrier frequency.
  • the digital signal with the second carrier frequency is transmitted to the frequency conversion module 205.
  • the frequency conversion module 205 is used to convert the digital signal processed by the second modulation module 204 to a set transmission frequency point so as to upload it to the narrowband satellite 1.
  • the encoding module 201 may be configured to encode the original data information based on cyclic encoding or convolutional encoding.
  • the first modulation module 202 and the second modulation module 204 may be based on one of digital phase modulation, multi-ary digital phase modulation, phase shift keying modulation, quadrature phase keying modulation, offset quadrature phase shift keying modulation Or a combination of multiple types to modulate the digital signal.
  • the filtering module 203 can be a digital shaping filter.
  • the digital shaping filter can eliminate inter-symbol interference, which can meet the Nyquist characteristic without inter-symbol interference, and can also smooth the waveform, which can accelerate the out-of-band attenuation speed of the modulated signal. To improve spectrum utilization.
  • the frequency conversion module 205 may be a programmable phase-locked loop chip.
  • the modulation signal can be converted to a set RF output frequency range, and then the frequency division interval can be set by setting Divide the available spectrum at equal frequency intervals into several carrier channels. Dividing the spectrum into multiple channels can improve the spectrum utilization. For example, if the available frequency band is 100.0000MHz to 100.0100MHz, and if the frequency division interval is 100Hz, the frequency band can be divided into 100 channels.
  • the narrowband signal can be obtained through the frequency conversion module. Furthermore, narrow-band multi-channel communication between the ground station 2 and the narrow-band satellite 1 is realized.
  • the ground station 2 may send the original data to the first modulation module 202 at a code rate of 600 bps after being encoded by the encoding module for modulation processing.
  • the first modulation module 202 transmits to the filter module 203 with a carrier frequency of 15 KHz to perform filter processing.
  • the second modulation module 204 remodulates the 15 KHz modulation signal so that it is transmitted to the frequency conversion module 205 at a carrier frequency of 10.685 MHz.
  • the first modulation module 202 is further configured to modulate the encoded signal processed by the encoding module 201 according to the following working mode:
  • S1 The coded signal undergoes serial-parallel conversion processing to generate a first branch code stream and a second branch code stream, where the first branch code stream and the second branch code stream are spaced apart from each other by setting codes Metacycle.
  • the respective code rates of the first tributary code stream and the second tributary code stream are two One in one.
  • the first tributary code stream can be transmitted in a serial transmission manner
  • the second tributary code stream can be transmitted in a parallel transmission manner.
  • the set symbol period may be a half symbol period. Either the first branch code stream or the second branch code stream can be shifted by half a symbol period after being delayed by half a symbol period. cycle.
  • the first filter 203a is a digital shaping filter.
  • the digital shaping filter may be a raised cosine roll-off filter. By controlling the roll-off coefficient, the shaped waveform of the encoded signal can be changed, thereby reducing the influence of sampling timing errors.
  • the frequency response H(f) of the raised cosine roll-off filter can be expressed by the following formula:
  • the corresponding time-domain waveform function is:
  • the symbol period T s 1/2f N , where f N is the Quinnest frequency.
  • ⁇ is the roll-off factor, which determines the shape of H(f), and ⁇ takes a value between [0, 1].
  • ⁇ is large, the time-domain waveform attenuation block and the oscillation fluctuation are small, which is beneficial to reduce the impact of inter-symbol interference and timing error, but the occupied frequency band becomes wider, the frequency band utilization rate is reduced, and the effect of in-band noise on the signal Will increase accordingly.
  • the roll-off factor ⁇ can be selected as 0.5, and the order of the digital shaping filter is set to 32.
  • the first modulation module 202 includes at least a first modulator 202a, a second modulator 202b, and a third modulator 202c.
  • the first modulator 202a is a quadrature modulator
  • the second modulator 202b and the third modulator 202c are both in-phase modulators.
  • the first branch code stream is transmitted to the first modulator 202a for orthogonal modulation processing to obtain a first modulated signal
  • the second branch code stream is transmitted to a second modulator for in-phase modulation processing to obtain a second modulated signal.
  • Both the first modulation signal and the second modulation signal are uniformly transmitted to the third modulator 202c for in-phase modulation processing to obtain a third modulation signal.
  • the first-stage modulation process can be performed by the first modulator 202a. By the second modulation its 202b and the third modulator 202c can perform a second-stage modulation process.
  • the third modulated signal is transmitted to the second filter 203b for filtering processing to complete the modulation processing of the encoded signal.
  • the second filter 203b is a band-pass filter that allows signals within a specific frequency range to pass, and can attenuate signals outside the specific frequency range to a very low level.
  • the coded signal is based on the modulation re-sampling process of the modulation module, which causes periodic extension of the signal spectrum and generates inter-symbol interference, which in turn leads to an increase in the error probability of the modulation module.
  • the order of the band-pass filter can be set to 64.
  • the processing of the band-pass filter can make the modulation envelope smoother.
  • the second-stage filtering process can be performed by the second filter 203b.
  • the first ground station 2a may send the first signal to the narrowband satellite 1, and then relay the first signal to the second ground station 2b through the narrowband satellite 1.
  • the second ground station 2b transmits the second signal to the narrow-band satellite
  • the second ground station 2b can simultaneously receive the echo of the second signal and the first signal as a combined signal.
  • the first ground station 2a can simultaneously receive the echo of the first signal and the second signal as a combined signal.
  • the first ground station 2a and the second ground station 2b can use the echo cancellation method to eliminate the interference caused by the echo. By canceling the echo, the demodulation of the first signal and the second signal can be facilitated.
  • the first signal and the second signal are subject to different environments and different degrees of interference during transmission, resulting in the combined signal received by the ground station requiring at least the transmitted signal, the echo of the transmitted signal, and the noise floor.
  • the transmission signal that needs to be transmitted refers to the first signal or the second signal that needs to be transmitted between the first ground station and the second ground station.
  • the noise floor refers to the sum of all noise sources and unwanted signals in the communication system, that is, any other signal except the transmitted signal.
  • the narrow-band satellite 1 includes at least a signal conditioning module 104.
  • the signal conditioning module 104 includes several filters to resolve, analyze, or suppress interfering signals on the combined signal.
  • the signal conditioning module 104 is configured to process the combined signal as follows:
  • the signal conditioning module 104 may include a fast Fourier transformer, and transmitting the combined signal to the fast Fourier transformer can implement the fast Fourier transform of the combined signal.
  • the fast Fourier transformer can add the product of the combined signal samples and the complex sinusoid of the frequency to obtain the frequency domain representation of the combined signal, where the processing process of the fast Fourier transformer can be expressed as: x n is the digital sample of the combined signal. N is the total number of samples being processed.
  • the output signal processed by the fast Fourier transform is decomposed to obtain multiple decomposed signals in different time-frequency spaces.
  • the output signal may be transmitted into the filter bank, and the filter bank may include several different filtering levels.
  • Each filtering level may include a low communication channel and a high communication channel, and the low communication channel and the high communication channel are each configured with a set of discrete wavelet transformers.
  • the output signal can be divided into subbands of different frequency bands.
  • the signals contained in different subbands can be decomposed into multiple different time-frequency spaces by the discrete wavelet transform processing of the discrete wavelet transformer.
  • the time-frequency content of the transmitted signal is separated from the frequency content of the interference signal.
  • the narrow-band satellite 1 includes at least an interference detection module 101, an interference cancellation module 102, and a demodulation module 103.
  • the narrowband satellite 1 may have a signal receiving module such as an antenna, and thus can receive signals transmitted by the ground station 2 or other signal terminals.
  • the interference detection module 101 is used to perform interference detection on signals in several different sub-bands output by the signal conditioning module 104, and thus can determine frequencies corresponding to all interference sources present in the combined signal.
  • the interference cancellation module 102 is configured to perform, for example, filtering processing on the interference source detected and determined by the interference detection module, so as to achieve interference cancellation.
  • the demodulation module 103 is used to demodulate the signal to facilitate further transmission of the signal.
  • the interference detection module 101 can calculate the average power of the combined signal and set a standard threshold.
  • the interference detection module analyzes and determines that the actual power of the combined signal is higher than the set standard threshold, it can be determined that there is interference.
  • the set value of the standard threshold can be determined in advance through the simulation of the interference signal in advance.
  • the interference cancellation module 102 may include an offset logic circuit 102a, a first multiplier 102b, a window function circuit 102c, a first fast Fourier transform circuit 102d, an interference cancellation circuit 102e, an inverse fast Fourier transform circuit 102f and signal correction circuit 102g.
  • the offset logic circuit 102a is used to align the frequency of the interference signal with the frequency center of the subcarrier of the communication channel.
  • the offset logic circuit can determine the frequency between the interference signal and the center frequency of the fast Fourier transform filter bank frequency ⁇ f The difference and the offset logic circuit can determine one or more of the frequency of the fast Fourier transform filter bank that is closest to the frequency of the interference signal.
  • the offset logic circuit can also create a first complex sinusoidal curve with respect to the received signal for performing multiplication of the analog signals with each other in the first multiplier 102b.
  • F s represents the sampling frequency.
  • N is the number of fast Fourier transform sampling points.
  • the first multiplier 102b may receive the first complex sinusoid and the combined signal from the offset logic circuit, where the combined signal contains sampled samples of the interference signal.
  • the first multiplier 102b multiplies the first complex sinusoid by the sampled sample to obtain the offset signal.
  • inter-carrier interference can also be introduced into the first multiplier 102b by multiplying the first complex sinusoid by the sampled samples.
  • the window function circuit 102c is used to receive the output of the first multiplier 102b and perform windowing processing on it.
  • the window function circuit may use, for example, a Hanning window function, a rectangular window function, or a Bartley window function to window the signal.
  • the first fast Fourier transform circuit 102d can receive the output of the window function circuit 102c and perform fast Fourier transform processing on it to generate a frequency domain signal.
  • the interference cancellation circuit 102e can receive the demodulated fast Fourier transform signal processed by the first fast Fourier transform circuit 102d, and the interference cancellation circuit 102e can use the offset logic circuit 102a in the fast Fourier transform signal during the calculation of ⁇ f
  • the determined subcarrier frequency is removed to obtain an interference cancellation signal.
  • the interference cancellation circuit 102e can set the frequency of the fast Fourier transform filter bank corresponding to the subcarrier frequency to zero. Since the frequency of the interference signal has been processed by the offset logic circuit 102a to be aligned with the frequency center of the subcarrier, and the frequency of the current subcarrier is set to zero by the interference cancellation circuit 102e, the interference signal is eliminated.
  • the interference cancellation signal can be transmitted to the inverse fast Fourier transform circuit 102f and is subjected to inverse fast Fourier transform processing to generate time-domain sampling samples.
  • the second complex sine curve generated by the correction circuit 102g and the output signal generated by the inverse fast Fourier transform circuit 102f are simultaneously transmitted to the second multiplier 102h for multiplication processing to eliminate inter-carrier interference.
  • the output signal of the second multiplier 102h can be transmitted to the second fast Fourier transform circuit 102i to perform fast Fourier transform processing again to demodulate the signal.
  • the output signal of the second fast Fourier transform circuit 102i is finally transmitted to the demodulation module 103 for decoding processing.
  • the first fast Fourier transform circuit 102d and the second fast Fourier transform circuit 102i jointly define a fast Fourier transform filter bank.
  • each narrow-band interference signal when each narrow-band interference signal is aligned with the frequency center of the sub-carrier of the communication channel, it will cause inter-carrier interference.
  • the signal will no longer carry the narrow-band interference after the sub-carrier frequency aligned with the narrow-band interference is removed, and then the inter-carrier interference is removed from the signal. Therefore, before decoding, the signal removes all narrow-band interference and any potential side lobes, thereby eliminating spectral leakage.
  • the encoding module 201 is further configured to encode the signal as follows:
  • S1 The BCH code generated by the signal after the BCH encoding process and the transmitted information frame form a set bit information subframe, where the bit length of the information subframe does not meet the set bit length, according to the supplementary 0 code Way to fill it.
  • the b-bit BCH code output can be obtained by encoding the a-bit signal through BCH(b, a), and the b-bit BCH code and the transmitted information frame form a c-bit information subframe.
  • b can be set to 31 and c can be set to 223.
  • the information subframe is synchronously scrambled.
  • the scrambling code is an n-pseudo-random sequence. Adding the linear feedback of the n-sequence to the data can balance the number of occurrences of the 0 code and the 1 code. It can convert the data into approximately white noise and reduce the spatial signal fading and bit error rate. .
  • the scrambling code period of the synchronous scrambling process can be set to 2 15 -1, the polynomial is 1+X 14 +X 15 , the n sequence of the starting register value is 1001_0101_0000_000, and all the data after the frame is scrambled .
  • S3 The subframes subjected to the scrambling process are sequentially subjected to RS encoding and convolutional encoding.
  • Convolutional coding has 1 input port and 2 output ports.
  • FIG. 6 shows the coding block diagram of the RS code.
  • the input information polynomial h(x) is divided by g(x) to obtain the remainder r(x), and r(x) is spliced to the tail of h(x) to obtain the output.
  • Codeword Specifically, h(x) is directly output through the gate A, and h(x) enters the RS verification circuit. At this time, the output of the verification circuit is disconnected. When all 223 elements enter the verification circuit, several registers are stored The data is the RS check digit. At this time, the output of the check circuit is open, and the check bit is output to complete r(x) splicing to the tail of h(x), thereby forming 255-bit RS coded data.
  • FIG. 7 shows a coding block diagram of a convolutional code.
  • the code rate is 3/4 bits/symbol
  • the constraint length is 7 bits
  • the output is determined by the puncturing scheme, where C1: 101, C2: 110, 1 represents the transmitted symbol, and 0 represents the symbol that is not transmitted.
  • the shift register is used to store bit information.
  • the output code stream sequence enters the shift register and divides the code stream sequence into two branches, and performs two XOR operations respectively.
  • the operation polynomial of the first branch is g1(x)
  • the operation polynomial of the second branch is g2(x).
  • the first branch and the second branch can send the operation results to the puncturing unit, where the operation results of the two branches enter the puncturing unit alternately, and the puncturing unit divides the continuous 6-bit data shift into a group, The order of entry for each group is C 1 (1)C 2 (1)C 1 (2)C 2 (2)C 1 (3)C 2 (3)... Finally, the puncturing unit performs convolution coding 3/4 puncturing and outputting on a set of data according to the puncturing scheme, and the output sequence is C 1 (1)C 2 (1)C 2 (2)C 1 (3)...
  • the data generated after convolutional encoding can be combined with a 320-bit carrier synchronization bit, a 160-bit pilot sequence, a 64-bit unique code, and a 64-bit frame tail to form a complete modulated data frame.
  • the resulting combined coding method has low bit error rate, high confidentiality, and high spectrum utilization.
  • the present invention may also be a satellite communication system based on suppressing narrow-band interference.
  • the narrow-band satellite 1 may also receive a combined signal composed of multiple component signals.
  • the combined signal may include a demand signal and an interference signal.
  • the demand signal refers to a signal that needs to be relayed and transmitted through the narrow-band satellite 1.
  • the narrowband satellite 1 further includes an analog-to-digital conversion module 105, a windowing module 106, a separation module 107, a regeneration module 108, a delay module 109, a cancellation module 110, and an inversion module 111.
  • Multi-channel transmission is established between the narrow-band satellite 1 and the ground station 2.
  • the signals transmitted by the multi-channel can have frequency overlap with each other, which can improve the utilization rate of spectrum resources.
  • the narrow-band satellite 1 is configured to perform separation processing on the combined signal with frequency overlap as follows:
  • S1 Perform windowing processing based on the windowing module 106 to obtain a window processing signal, and perform nth power processing on the window processing signal based on the interference detection module 101 to determine the modulation characteristic of the component signal and the symbol rate of the carrier corresponding to the component signal.
  • the analog-to-digital conversion module 105 is used to perform analog-to-digital conversion on the combined signal received by the narrowband satellite to convert the analog signal into a digital signal.
  • the combined signal received by the narrowband satellite 1 is first transmitted to the analog-to-digital conversion module 105 for analog-to-digital conversion processing to generate a digital signal.
  • the windowing module 106 can receive the digital signal generated by the analog-to-digital conversion module 105.
  • the windowing module 106 can limit the bandwidth of the digital signal or pay attention to a part of the digital signal to ensure that it can effectively process the spectrum part of the demand signal, and then can Generate window processing signals.
  • the interference detection module 101 can receive the window processing signal and identify and determine its signal components.
  • the interference detection module 101 may be configured to perform n-th power processing on the window processing signal until it is converted into a continuous wave.
  • the window processing signal contains a variety of different signals, for example, it may contain two demand signals and three interference signals. Different signals have different modulation characteristics, and thus can form multiple different n-th power processing, that is, the window
  • the processed signal may obtain a continuous wave when performing the fourth power processing, and another continuous wave when performing the eighth power.
  • the window processing signal with 5 kinds of signals can generate 5 continuous waves independent of each other in 5 different nth powers.
  • the n-th power processing is executed in multiples of 2, that is, the power-of-two processing, power-of-four processing, power-of- six processing, etc. can be executed.
  • the n-th power processing when the n-th power processing is performed, it is performed in a manner that each stage is incremented by 2 stages.
  • the modulation characteristic of the component signal can be determined at least by one or more of phase offset, frequency offset, bandwidth and time delay of the component signal.
  • the waveform of the continuous wave formed after the nth power processing can determine the phase offset, frequency offset, bandwidth and time delay.
  • the symbol rate of the window processing signal may be determined based on the nth power processing process of the window processing signal. For example, when the signal is performing n-th power processing, the phases of the symbols will be correlated or the correlation between them will be eliminated, and then a continuous wave represented by a single frequency in the frequency domain can be formed. This process can produce a distribution. For the small side lobes around the frequency of the continuous wave, the interval between the small side lobes is related to the symbol rate of the carrier of the corresponding component signal, and the symbol rate of the carrier can be determined based on the interval between the small side lobes.
  • the separation module 107 resamples the window processing signal in a manner based on m times of the symbol rate to generate a resampled signal, and determines at least One symbol track and at least one modulation type.
  • the window processing signal may be transmitted to the separation module 107, and the separation module may process the signal in a manner of m times the symbol rate based on the determined modulation characteristics Resample. That is, the separation module 107 samples its received signal at a higher rate, and can then derive the symbol trajectory, shaping factor, and modulation type.
  • the shaping factor can be used to evaluate the degree of concentration or dispersion of signal energy.
  • the shaping factor may be the root-raised cosine spectrum of the window processed signal.
  • signals with different components can generate multiple continuous waves in different n-th power processing.
  • a continuous wave when using binary phase keying to modulate a signal, a continuous wave can be generated when the power is processed twice.
  • quadrature phase shift keying when using quadrature phase shift keying to modulate the signal, continuous waves can be generated during the fourth power processing. Therefore, the modulation type of the signal can be determined according to the number of times of self-multiplication processed by the nth power.
  • the value of m may be an integer greater than 2.
  • the regeneration module 108 synthesizes each component signal based on at least one symbol trajectory and at least one modulation type to generate a composite signal.
  • the inversion module 111 performs inversion processing on the composite signal
  • the delay module 109 delays the transmission of the copy of the digital signal to the cancellation module 110, and the cancellation module 110 superimposes the inverted copy with the copy of the digital signal to eliminate the interference signal, thereby obtaining the first-level interference Suppress the signal.
  • the first-level interference suppression signal can be transmitted to the signal preprocessing module 101 for processing to separate the time-frequency content of the transmitted signal from the frequency content of the interference signal.
  • the first-level interference suppression signal processed by the signal preprocessing module 101 can be transmitted to the interference cancellation module 102 to further eliminate the interference signal.

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Abstract

La présente invention concerne un système de communication par satellite à canaux multiples à bande étroite, dans lequel un signal est transmis à au moins un satellite à bande étroite au moyen d'une station au sol, la station au sol comprenant au moins un module de codage et un premier module de modulation et la station au sol étant configurée comme il suit : le module de codage est configuré pour coder un signal de façon à acquérir un signal codé ; et le premier module de modulation est configuré pour exécuter une conversion série-parallèle sur le signal codé de façon à générer un premier flux binaire de ramification et un second flux binaire de ramification, un traitement de retard étant exécuté dans le premier flux binaire de ramification de telle sorte que, dans la situation dans laquelle une période d'élément de code est établie entre le premier flux binaire de ramification et le second flux binaire de ramification à des intervalles, le premier flux binaire de ramification exécute séquentiellement un traitement de filtre de premier niveau et un traitement de modulation de premier niveau pour acquérir un premier signal modulé et le second flux binaire de ramification exécute un traitement de filtre de premier niveau et un traitement de modulation de second niveau pour acquérir un deuxième signal modulé ; et le premier signal modulé et le deuxième signal modulé subissent conjointement un traitement de modulation de second niveau de façon à obtenir un troisième signal modulé, le troisième signal modulé subissant un traitement de filtre de second niveau pour terminer le traitement de modulation.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111812682A (zh) * 2020-07-24 2020-10-23 华力智芯(成都)集成电路有限公司 一种抗窄带干扰电路
CN113824488A (zh) * 2021-09-09 2021-12-21 中国电子科技集团公司第五十四研究所 基于判决反馈自适应对消的卫星通信非恶意干扰抑制方法
CN114499736A (zh) * 2020-11-12 2022-05-13 晶晨半导体(上海)股份有限公司 去除WIFI系统spur干扰的方法、计算机存储介质和宽带系统
US11999380B1 (en) * 2021-12-17 2024-06-04 Zoox, Inc. Autonomous vehicle trajectory generation and optimization

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101154983A (zh) * 2006-09-27 2008-04-02 上海微小卫星工程中心 一种基于单倍采样的卫星通信抗干扰技术的实现方法
WO2010080841A1 (fr) * 2009-01-06 2010-07-15 Qualcomm Incorporated Transmission à ondes porteuses multiples sur une bande de fréquence unique
CN107872268A (zh) * 2016-09-26 2018-04-03 北京大学（天津滨海）新代信息技术研究院 一种用于卫星通信系统消除干扰的方法
CN109698712A (zh) * 2018-12-28 2019-04-30 长沙天仪空间科技研究院有限公司 窄带卫星通信系统
CN109768823A (zh) * 2018-12-28 2019-05-17 长沙天仪空间科技研究院有限公司 一种窄带多通道卫星通信系统
CN109802719A (zh) * 2019-01-03 2019-05-24 长沙天仪空间科技研究院有限公司 一种基于抑制窄带干扰的卫星通信系统

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100596129C (zh) * 2005-10-13 2010-03-24 北京泰美世纪科技有限公司 一种多载波数字卫星广播系统及其数字信息传输方法
CN105978664B (zh) * 2016-06-24 2019-01-25 中国科学院国家空间科学中心 一种用于遥感卫星的有效载荷数据传输系统

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101154983A (zh) * 2006-09-27 2008-04-02 上海微小卫星工程中心 一种基于单倍采样的卫星通信抗干扰技术的实现方法
WO2010080841A1 (fr) * 2009-01-06 2010-07-15 Qualcomm Incorporated Transmission à ondes porteuses multiples sur une bande de fréquence unique
CN107872268A (zh) * 2016-09-26 2018-04-03 北京大学（天津滨海）新代信息技术研究院 一种用于卫星通信系统消除干扰的方法
CN109698712A (zh) * 2018-12-28 2019-04-30 长沙天仪空间科技研究院有限公司 窄带卫星通信系统
CN109768823A (zh) * 2018-12-28 2019-05-17 长沙天仪空间科技研究院有限公司 一种窄带多通道卫星通信系统
CN109802719A (zh) * 2019-01-03 2019-05-24 长沙天仪空间科技研究院有限公司 一种基于抑制窄带干扰的卫星通信系统

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111812682A (zh) * 2020-07-24 2020-10-23 华力智芯(成都)集成电路有限公司 一种抗窄带干扰电路
CN114499736A (zh) * 2020-11-12 2022-05-13 晶晨半导体(上海)股份有限公司 去除WIFI系统spur干扰的方法、计算机存储介质和宽带系统
CN114499736B (zh) * 2020-11-12 2024-03-08 晶晨半导体(上海)股份有限公司 去除WIFI系统spur干扰的方法、计算机存储介质和宽带系统
CN113824488A (zh) * 2021-09-09 2021-12-21 中国电子科技集团公司第五十四研究所 基于判决反馈自适应对消的卫星通信非恶意干扰抑制方法
CN113824488B (zh) * 2021-09-09 2022-07-08 中国电子科技集团公司第五十四研究所 基于判决反馈自适应对消的卫星通信非恶意干扰抑制方法
US11999380B1 (en) * 2021-12-17 2024-06-04 Zoox, Inc. Autonomous vehicle trajectory generation and optimization

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