CN111970002A - Atomic clock remote frequency transmission and comparison method based on Beidou GEO satellite - Google Patents
Atomic clock remote frequency transmission and comparison method based on Beidou GEO satellite Download PDFInfo
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Abstract
The invention provides an atomic clock remote frequency transmission and comparison method based on a Beidou GEO satellite. The downlink carrier doppler velocity measurement information received simultaneously by the primary and secondary stations carries the reference frequency accuracy deviation information of the primary and secondary stations, which reflects the accuracy of the output frequency of each atomic clock serving as a frequency reference. Therefore, the accurate calculation of the frequency accuracy deviation information of the primary station and the secondary station can be used for frequency compensation and calibration of the low-accuracy atomic clock, and the unification of frequency references is completed in the full measurement and control network system.
Description
Technical Field
The invention belongs to the field of aerospace measurement and control, and particularly relates to a remote frequency transmission and comparison method for an atomic clock.
Background
At present, the frequency reference of all measurement and control stations in the aerospace measurement and control network in China is mainly provided by atomic clocks equipped in respective time-frequency systems. Due to the fact that the technology and the process adopted by the atomic clock system are different and the working environment is different, the stability and the accuracy of the frequency reference according to different stations are inconsistent.
Common remote high-precision time-frequency transmission means include GNSS common view-based time frequency calibration, satellite bidirectional time frequency transmission, optical fiber time-frequency signal transmission and the like. And based on GNSS common view time frequency calibration, the time frequency calibration is realized through time comparison. The method belongs to passive receiving, has simple equipment and relatively lagged processing time, and needs one party to transmit data to the other party for processing so as to obtain a final processing result and feed the result back to the party transmitting the data. The satellite bidirectional time frequency transmission also adopts a time comparison mode to realize the acquisition of a high-precision time frequency result. The method has good real-time performance, can eliminate a plurality of system errors, but needs special satellite cooperation, and equipment needs to have the receiving and transmitting functions. Neither of the above methods utilizes characteristic information such as the carrier's own frequency. The transmission of optical fiber time-frequency signals has the advantages of large capacity, high transmission precision and the like, and is an important means of ground high-precision time-frequency transmission, but the transmission precision is difficult to maintain during long-distance time-frequency signal transmission due to the fact that the optical fiber transmission is sensitive to the influence of weather environmental factors such as temperature, vibration and the like, so that the optical fiber transmission is mostly applied to the distance range of hundreds of kilometers, and at present, no special frequency transmission optical fiber network for long distance is provided at home.
In the deep space three-way speed measurement, the master station and the secondary station adopt a common view GPS to process the frequency deviation between the stations. The hydrogen clock configured in the deep space station has relatively high frequency accuracy, short stability and normal stability (10)-13Magnitude), smoothing is carried out by using the co-view GPS data to measure frequency deviation between stations, 24h of data is needed for smoothing at first, and three-way speed measurement errors caused by frequency deviation between stations can be deducted by using the frequency deviation between stations, so that the three-way speed measurement precision is improved.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides an atomic clock remote frequency transmission and comparison method based on a Beidou GEO satellite. The downlink carrier doppler velocity measurement information received by the primary and secondary stations simultaneously carries the accuracy deviation information of the reference frequency of the primary and secondary stations (since the deviation of the reference frequency is compared, the calculation according to the two steps in fig. 1 can be known). The reference frequency accuracy deviation information reflects the accuracy of each atomic clock output frequency as a reference for providing a frequency. Therefore, the accurate calculation of the frequency accuracy deviation information of the primary station and the secondary station can be used for frequency compensation and calibration of the low-accuracy atomic clock, and the unification of frequency references is completed in the full measurement and control network system.
The technical scheme adopted by the invention for solving the technical problem comprises the following steps:
step 2, the master station is used for sending uplink carriers to the selected Beidou GEO satellite (any measurement and control equipment unit which sends uplink signals in the measurement and control network is selected as the master station);
step 3, the Beidou GEO satellite performs coherent forwarding on the received uplink carrier;
step 4, the master station and the secondary station simultaneously receive downlink carriers transmitted by the Beidou GEO satellite and store Doppler velocity measurement data;
step 5, resolving the Doppler velocity measurement data stored in the step 4 through the established frequency source frequency deviation model; the frequency source frequency deviation model comprises the influence of troposphere and ionosphere delay on frequency components in a link and the influence of relative motion of a satellite and a master station and a slave station on frequency;
and 6, performing least square linear fitting on the calculation results of the master station and the slave station in the step 5 and comparing the results with the difference values to extract frequency accuracy deviation, so as to realize remote frequency transmission and comparison of the atomic clock.
In step 5, if the uplink carrier frequency f sent by the master station a isA，CFrequency deviation f of the atomic clock of the secondary station relative to the atomic clock of the primary stationA,clk-fB,clk＝fB,dop-(fA,ion+fA,trop+fA,d+A+fB,ion+fB,trop+fB,d+B) Wherein the influence of the ionospheric delay of the uplink between the master station and the satellite in the frequency direction is fA，ionThe effect of tropospheric delay in the frequency direction is fA，tropThe influence of the relative motion of the main station and the satellite in the frequency direction is fA，d，AFor the effect of other errors in frequency, the ionospheric delay experienced by the downlink between the secondary station B and the satellite in the frequency direction has the effect fB，ionThe effect of tropospheric delay in frequency is fB，tropThe Doppler caused by the relative motion of the secondary station equipment and the satellite is fB，d，BFor the influence of other errors in frequency, the downlink comprehensive Doppler frequency shift actually recorded by the B station equipment is fB,dop。
In the step 5, if the frequency reference station is the secondary station B, the primary station a sends an uplink carrier signal to the beidou GEO for coherent forwarding, and the primary station a, the secondary station B and the secondary station C simultaneously receive the uplink carrier signal sent by the primary station, the frequency deviation of the atomic clock of the secondary station C relative to the atomic clock of the secondary station B
fC，clk-fB，clk＝-[fC，dop-fC，ion-fC，trop-fC，d-C-(fB，dop-fB，ion-fB，trop-fB，d-B)]
Wherein, the downlink comprehensive Doppler frequency shift actually recorded by the secondary station B is fB，dopThe effect of ionospheric delay in the frequency direction experienced by the downlink between the secondary station B and the satellite is fB，ionThe effect of tropospheric delay in frequency is fB，tropThe Doppler caused by the relative motion of the secondary station equipment and the satellite is fB，d，BFor the effect of other errors in frequency, the ionospheric delay experienced by the downlink between the secondary station C and the satellite in the frequency direction has the effect fC，ionThe effect of tropospheric delay in frequency is fC，tropThe Doppler caused by the relative motion of the secondary station C and the satellite is fC，d，CThe actual received downlink combined Doppler shift f of secondary station C for the effect of other errors in frequencyC，dop。
The invention has the beneficial effects that: the Doppler speed measurement data of the downlink carrier signals forwarded by the same Beidou GEO satellite is received by the primary station and the secondary station at the same time, and the Doppler data information carries the characteristic of reflecting the accuracy deviation information of the reference frequency of the primary station and the secondary station. The method corrects the transmission error quantity in the frequency domain, the frequency domain error analysis and processing process is simpler than the time domain under the same system precision requirement, the transmission chain error analysis time is greatly shortened, and the online calibration of the frequency accuracy of the atomic clock to be corrected can be realized according to the calculated frequency accuracy deviation of each test station and the frequency reference station, so that the frequency accuracy of the atomic clock in the measurement and control network can be improved to the level of the hydrogen atomic clock of the frequency reference station, and the frequency accuracy of the atomic clock in the measurement and control system can be improved and unified. The system provided by the invention does not need to transform a hardware part, has simple and clear transmission and comparison modes, and can provide powerful technical and method support for improving and unifying the frequency reference of the aerospace measurement and control network based on the performance of the existing equipment.
Drawings
Fig. 1 is a system configuration diagram of the present invention, in which (a) is a system configuration diagram in which a primary station is a frequency reference station, and (b) is a system configuration diagram in which a secondary station is a frequency reference station.
Fig. 2 is 14: 44: 04-16: 31: 25, directly differentiating the results, wherein (a) the secondary station 1 acquires downlink doppler data, (b) the secondary station 2 acquires downlink doppler data, and (c) the direct differentiation result is a hydrogen clock-rubidium clock.
Fig. 3 is 15: 13: 57-15: 21: 49 base bands of three stations acquire a Beidou downlink comprehensive Doppler shift result graph, wherein (a) downlink Doppler shift is acquired for the secondary station 1, (b) downlink Doppler shift is acquired for the secondary station 2, and (c) Beidou downlink Doppler shift data is acquired for the primary station.
Fig. 4 is a diagram showing the comparison result of the performance of the rubidium atomic clock of the secondary station 2 and the hydrogen atomic clock of the primary station.
FIG. 5 is a graph showing the comparison of the performance of the hydrogen atomic clock of the secondary station 1 and the hydrogen atomic clock of the primary station.
Fig. 6 is a graph of the performance ratio of the rubidium atomic clock of the sub-station 2 to the hydrogen atomic clock of the sub-station 1.
FIG. 7 is a diagram of a 10MHz direct frequency transfer test system for a primary station hydrogen atomic clock and a secondary station rubidium atomic clock.
Fig. 8 is 11: 25: 38-12: 58: 34 direct differential data processing results plot, where the abscissa is time interval (seconds) and the ordinate is frequency (Hz).
Fig. 9 is 16: 43: 19-21: 40: 15 direct differencing process results plot, where the abscissa is time interval (seconds) and the ordinate is frequency (Hz).
Detailed Description
The present invention will be further described with reference to the following drawings and examples, which include, but are not limited to, the following examples.
The implementation process of the embodiment of the invention comprises the following steps: 1) the measuring and controlling equipment based on the Beidou GEO satellite is composed of a hydrogen atomic clock remote frequency transmission and comparison system; 2) the remote frequency transmission satellite-ground link error analysis and frequency source frequency deviation model establishment of the hydrogen atomic clock of the measurement and control equipment; 3) and testing and verifying the remote frequency transmission and comparison system of the measurement and control equipment. The method comprises the following specific steps:
step one, setting a hydrogen atomic clock remote frequency transmission and comparison system of the measurement and control equipment based on the Beidou GEO satellite according to the figure 1 to form an experimental scene. Firstly, selecting measurement and control equipment with bidirectional or three-way measurement capability and equipped with an atomic clock as a measurement and control unit capable of carrying out remote frequency transmission on the ground, and dividing the measurement and control unit into a main station device (having a function of transmitting uplink carrier waves and a function of receiving data of Doppler velocity measurement of downlink carrier waves) and a secondary station (having a function of receiving data of Doppler velocity measurement of downlink carrier waves) according to functions borne by each device in a frequency transmission system. A station containing a high-precision hydrogen atomic clock is designated as a frequency reference station (both a main station and a secondary station). And secondly, determining a carrier signal transmission flow, and sending uplink carriers to the selected Beidou GEO satellite by the master station equipment.
And step two, the Beidou GEO satellite locks and coherently forwards the downlink carrier after receiving the transmitted uplink carrier, and the master station and the secondary station simultaneously receive the downlink carrier, lock the 70MHz intermediate frequency and simultaneously receive downlink Doppler frequency shift data. The frequency of the ground atomic clock is set to be 10MHz offset 1KHz, and the downlink Doppler velocity measurement data is stored.
And step three, processing the Doppler velocity measurement data obtained in the step two, and resolving through the established frequency source frequency deviation model. Referring to fig. 1(a), in experiment 1, when the frequency reference station is a master station, the master station transmits an uplink carrier and receives downlink doppler velocity measurement data forwarded by a beidou GEO, where the downlink doppler velocity measurement data includes frequency accuracy information of a local atomic clock, and the doppler frequency data recorded by the master station deducts influences of troposphere and ionosphere delay of a downlink of the master station on frequency components and influences of relative motion of a satellite and the master station on frequency, and then deducts doppler caused by the troposphere and the ionosphere, and the relative motion of the satellite and the test station of the downlink station compared with the influence of the relative motion of the satellite and the test station. The constant term of the first-order fitting result of the residual Doppler corresponds to the frequency accuracy of the measured atomic clock relative to the reference atomic clock, and the first term reflects the drift rate of the measured atomic clock relative to the reference atomic clock.
The specific calculation process is as follows:
the main station (A) transmits an uplink carrier frequency fA，CThe effect of ionospheric delay of the uplink between the master station and the satellite in the frequency direction is fA，ionThe effect of tropospheric delay in the frequency direction is fA，tropThe influence of the relative motion of the main station and the satellite in the frequency direction is fA，d，fA，clkIs a frequency component of an atomic clock and,Athe effect of other errors in frequency. Because of coherent forwarding, the uplink carrier frequency actually received by the satellite is the same regardless of the influence of the satellite clock
fS，C＝fA，C+fA，ion+fA，trop+fA，d+fA，clk+A (1)
When the satellite receives the uplink signal, the coherent retransmission is carried out, and at the moment, the secondary station (B) receives the downlink signal. Suppose that the effect of ionospheric delay in the frequency direction experienced by the downlink between the secondary station and the satellite is fB，ionThe effect of tropospheric delay in frequency is fB，tropThe Doppler caused by the relative motion of the secondary station equipment and the satellite is fB，d，BFor the effect of other errors in frequency, the frequency component of the B station atomic clock is fB，clkIf the actual downlink carrier frequency received by the secondary station is:
fB,C＝fS,C+fB,ion+fB,trop+fB,d+B (2)
bringing formula (1) into formula (2)
fB,C＝fA,C+fA,ion+fA,trop+fA,d+fA,clk+A+fB,ion+fB,trop+fB,d+B (3)
fA，CUplink carrier frequency, f, for A station equipment transmissionB，CFor the downlink carrier frequency with Doppler actually measured by the B station equipment, the influence of the ionosphere, the troposphere and the relative motion on the frequency components of the receiving links of the two stations can be respectively calculated, and the downlink comprehensive Doppler frequency shift f actually recorded by the B station equipmentB，dop＝fB，C-fA，C，
fB,dop＝fB,C-(fB+fB,clk) (4)
fBIs the comparison frequency of the theoretical standard of the B station, and the value is equal to fA，C. Putting the formula (3) into the formula (4) and finishing to obtain
fA,clk-fB,clk＝fB,dop-(fA,ion+fA,trop+fA,d+A+fB,ion+fB,trop+fB,d+B) (5)
fA，clk＝fB，clkIs the frequency deviation of the slave atomic clock relative to the master atomic clock.
Referring to fig. 1(b), when the frequency reference station is a secondary station, the downlink doppler frequency shift includes, in addition to the doppler frequency shift caused by the relative motion between the respective station and the satellite, the ionosphere and the troposphere, and the information of the local clock, the performance factor of the uplink station clock, the relative motion between the uplink station and the satellite, the doppler frequency shift caused by the uplink station transmission signal link, the ionosphere, and the troposphere, so that when processing the data of the two stations, the two downlinks first consider to subtract the relative motion between the respective station and the satellite, the influence factors of the troposphere and the ionosphere, and finally, the two downlinks are differentiated by calculating the results, so as to subtract the information of the uplink station clock, and the influence factors of various errors in the frequency components, and the residual doppler is considered as the difference in the atomic clock frequency accuracy of the two different receiving stations.
The specific calculation process is as follows:
the master station (A) is arranged to send uplink carrier signals to the Beidou GEO for coherent forwarding, the master station (A), the secondary station 1(B, the frequency reference station) and the secondary station 2(C) receive the uplink carrier signals sent by the master station simultaneously, and all station devices acquire and record downlink Doppler velocity measurement data. Downlink comprehensive Doppler frequency shift f actually recorded by secondary station 1(B, frequency reference station) equipmentB，dopIs composed of
fB,dop＝fB,C-(fB+fB,clk) (6)
The secondary station 2(C) station assumes that the influence of ionospheric delay in the frequency direction on the downlink between the secondary station and the satellite is fC，ionThe effect of tropospheric delay in frequency is fC，tropThe Doppler caused by the relative motion of the secondary station 2(C) equipment and the satellite is fC，d，CFor the effect of other errors in frequency, the frequency component of the C station atomic clock is fC，clkThen, the downlink carrier frequency f actually received by the secondary station 2(C) deviceC,CAnd for the downlink integrated Doppler shift fC，dop：
fC,C＝fS,C+fC,ion+fC,trop+fC,d+C (7)
fC,dop＝fC,C-(fC+fC,clk) (8)
Subtracting the expressions (6) and (7) to obtain the frequency deviation of the atomic clock of the secondary station 2 relative to the atomic clock of the secondary station 1 (frequency reference station) as follows:
fC，clk-fB，clk＝-[fC，dop-fC，ion-fC，trop-fC，d-C-(fB，dop-fB，ion-fB，trop-fB，d-B)] (9)
step four, performing data fitting and comparison on the resolving results of the master station and the slave station in the step three to extract frequency accuracy deviation, and realizing remote frequency transmission of the atomic clockAnd (5) comparing. Obtaining a final frequency-time sequence f through satellite-ground link error analysis and the calculation of the corrected frequency linki(t), fitting the frequency difference equation after error correction in the observation period by adopting least square normative, and recording a zero point result f (t)0)，
Frequency accuracy was calculated at 1 day intervals, using the average of the frequency accuracy for 7 consecutive days.
All frequency difference data f (t) are divided into units of daysi) After error correction is carried out, linear fitting is carried out on the N sampling values by adopting a least square method, and the specific fitting method is shown as the following formula:
by mean of points
Making a straight line, namely the frequency difference equation, as follows:
the zero point result after fitting is recorded as
Continuously recording for 7 days
The frequency accuracy A is calculated by the formula:
average of calculated frequency accuracies over 7 days
As a final evaluation result.
And fifthly, testing and verifying the remote frequency transmission and comparison system of the measurement and control equipment. The method comprises the steps of analyzing and processing the mutual comparison results of the three station atomic clocks, and verifying the effectiveness and the suitability based on the method by constructing a closed link.
Referring to fig. 1(a), 3 stations are selected for carrying out closure test verification, namely a main station (hydrogen atomic clock station), a secondary station 1 (hydrogen atomic clock station) and a secondary station 1 (rubidium atomic clock station). The experimental scheme is shown in table 1, where the primary station is about 4000 km from the secondary station and the secondary station 1 is about 200 m from the secondary station 2.
TABLE 1 test protocol
TABLE 2 data acquisition recording time period
Referring to fig. 1(a), the master station transmits an uplink signal to the big dipper GEO satellite, the secondary station 1 and the secondary station 2 receive big dipper downlink doppler frequency shift data at 70MHz intermediate frequency, and the ground atomic clock frequency is set to be 10MHz offset 1 KHz. And recording and storing the respective baseband data. The first period of data time is 14: 44: 04-14: 52: 52, the second period of data time is 15: 13: 56-15: 21: 49, the third segment data time is 15: 29: 28-16: 31: 25. considering that the distance between the two sets of equipment of the secondary station 1 and the secondary station 2 is about 200 meters, the influences caused by troposphere delay, ionosphere delay and perturbation of geosynchronous stationary orbit satellites are consistent, a direct difference method is adopted to solve frequency deviation, the first method adopts a direct difference method to process, the influence of the factors is ignored, and the deviation of downlink Doppler frequency values received by the two sets of systems is considered to be the difference between the accuracy of a hydrogen atomic clock and the accuracy of a rubidium atomic clock. After the test data is received and recorded, the downlink Doppler velocity measurement data is analyzed and processed, and then the remote frequency transmission and comparison of the atomic clock can be completed.
Referring to fig. 7, it is a diagram of a direct frequency transfer test system of a sub-station 1 hydrogen atomic clock and a sub-station 2 rubidium atomic clock. Through a low-loss cable, a rubidium clock time-frequency signal of the secondary station 2 device is directly compared with a hydrogen atomic clock time-frequency signal of the secondary station 1 device through an RSR receiver. The RSR receiver introduces a 10MHz signal output by a hydrogen atomic clock of the secondary station 1 as a time-frequency 1pps reference. The hydrogen atomic clock of the sub-station 1 is set to be 10MHz offset 1KHz, the rubidium atomic clock of the sub-station 2 is set to be 10MHz offset 1KHz, and the RSR receiver respectively collects and records Doppler frequency shift and phase data. The set of tests is used for comparing data analysis results with the Beidou transmitted frequency transmission process, and is used for verifying the effectiveness of the remote frequency transmission and comparison method. Fig. 8 is 11: 25: 38-12: 58: 34 direct differencing of the data processing results, where the abscissa is the time interval (seconds) and the ordinate is the frequency (Hz).
The results of the different baseline length frequency transfer tests are shown in table 3. Considering that the frequency readiness degree calculated by the current system is in the order of 10e-12, the measurement error of other transmission delays is 10 due to the quantity value solved on the frequency component-14And below, and are therefore ignored. And only three types of errors are accurately calculated and deducted, and other transmission time delays on a transmission path are gradually added to the accurate calculation of frequency components in subsequent high-precision calculation.
Table 3 different base line length frequency transfer test results
As can be seen from table 3:
1. the direct transmission accuracy of the atomic clock frequency at a baseline of 200 meters is consistent with the transmission accuracy of the frequency forwarded by the Beidou.
2. The frequency accuracy obtained by adopting a direct differential data processing mode and an error-corrected data processing mode is consistent, and the reliability of the drift rate is increased along with the increase of the test time.
3. The data processing result of the test 3 meets the following relational expression, and the system precision reaches the e-12 magnitude:
Δfsub 1-sub 2＝ΔfPrimary-secondary 2+ΔfPrimary-secondary 1 (27)
According to the test results, the accuracy calculation method is correct, the satellite-ground link error correction model is appropriate, the effect is obvious, and the remote frequency transmission and comparison of the atomic clock in the measurement and control system can be well realized through the coherent forwarding of the Beidou GEO satellite.
Claims (3)
1. A Beidou GEO satellite-based atomic clock remote frequency transmission and comparison method is characterized by comprising the following steps:
step 1, firstly, selecting a measurement and control device which has bidirectional or three-way measurement capability and is provided with an atomic clock as a measurement and control unit which can carry out remote frequency transmission on the ground;
step 2, the master station is used for sending uplink carriers to the selected Beidou GEO satellite (any measurement and control equipment unit which sends uplink signals in the measurement and control network is selected as the master station);
step 3, the Beidou GEO satellite performs coherent forwarding on the received uplink carrier;
step 4, the master station and the secondary station simultaneously receive downlink carriers transmitted by the Beidou GEO satellite and store Doppler velocity measurement data;
step 5, resolving the Doppler velocity measurement data stored in the step 4 through the established frequency source frequency deviation model; the frequency source frequency deviation model comprises the influence of troposphere and ionosphere delay on frequency components in a link and the influence of relative motion of a satellite and a master station and a slave station on frequency;
and 6, performing least square linear fitting on the calculation results of the master station and the slave station in the step 5 and comparing the results with the difference values to extract frequency accuracy deviation, so as to realize remote frequency transmission and comparison of the atomic clock.
2. The atomic clock remote frequency transmission and comparison method based on the Beidou GEO satellite according to claim 1, characterized in that: in step 5, if the uplink carrier frequency f sent by the master station a isA，CThe atomic clock of the secondary station is opposite to the primary stationFrequency deviation f of atomic clockA,clk-fB,clk＝fB,dop-(fA,ion+fA,trop+fA,d+A+fB,ion+fB,trop+fB,d+B) Wherein the influence of the ionospheric delay of the uplink between the master station and the satellite in the frequency direction is fA，ionThe effect of tropospheric delay in the frequency direction is fA，tropThe influence of the relative motion of the main station and the satellite in the frequency direction is fA，d，AFor the effect of other errors in frequency, the ionospheric delay experienced by the downlink between the secondary station B and the satellite in the frequency direction has the effect fB，ionThe effect of tropospheric delay in frequency is fB，tropThe Doppler caused by the relative motion of the secondary station equipment and the satellite is fB，d，BFor the influence of other errors in frequency, the downlink comprehensive Doppler frequency shift actually recorded by the B station equipment is fB,dop。
3. The atomic clock remote frequency transmission and comparison method based on the Beidou GEO satellite according to claim 1, characterized in that: in the step 5, if the frequency reference station is the secondary station B, the primary station a sends an uplink carrier signal to the beidou GEO for coherent forwarding, and the primary station a, the secondary station B and the secondary station C simultaneously receive the uplink carrier signal sent by the primary station, the frequency deviation f of the atomic clock of the secondary station C relative to the atomic clock of the secondary station BC，clk-fB，clk＝-[fC，dop-fC，ion-fC，trop-fC，d-c-(fB，dop-fB，ion-fB，trop-fB，d-B)]
Wherein, the downlink comprehensive Doppler frequency shift actually recorded by the secondary station B is fB，dopThe effect of ionospheric delay in the frequency direction experienced by the downlink between the secondary station B and the satellite is fB，ionThe effect of tropospheric delay in frequency is fB，tropThe Doppler caused by the relative motion of the secondary station equipment and the satellite is fB，d，BIonospheric delay experienced by the downlink between the secondary station C and the satellite for the frequency of other errorsThe influence in the frequency direction is fC，ionThe effect of tropospheric delay in frequency is fC，tropThe Doppler caused by the relative motion of the secondary station C and the satellite is fC，d，CThe actual received downlink combined Doppler shift f of secondary station C for the effect of other errors in frequencyC，dop。
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112540388A (en) * | 2020-11-24 | 2021-03-23 | 湖北三江航天险峰电子信息有限公司 | Satellite communication module and uplink signal Doppler compensation method thereof |
| CN113507323A (en) * | 2021-06-17 | 2021-10-15 | 西安空间无线电技术研究所 | Inter-satellite frequency transmission system and method based on active phase noise compensation |
| CN114785651A (en) * | 2022-06-21 | 2022-07-22 | 中国人民解放军国防科技大学 | Doppler frequency shift elimination method and system for bidirectional frequency transmission |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5995040A (en) * | 1995-11-14 | 1999-11-30 | Centre National D'etudes Spatiales | Global space radiopositioning and radionavigation system, beacon and receiver used in this system |
| CN102338873A (en) * | 2011-09-28 | 2012-02-01 | 中国电子科技集团公司第十研究所 | Method for integrally telemetering and ranging target range aircraft |
| CN107994920A (en) * | 2017-11-22 | 2018-05-04 | 南京理工大学 | A kind of cube Satellite TT answering machine and its coherent signal retransmission method |
| CN108134625A (en) * | 2017-12-11 | 2018-06-08 | 北京无线电计量测试研究所 | A kind of two-way satellite time and frequency transfer method |
| CN108845338A (en) * | 2018-07-26 | 2018-11-20 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | Star ground united carrier smoothing pseudo range distance measuring method |
-
2020
- 2020-08-10 CN CN202010795269.9A patent/CN111970002B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5995040A (en) * | 1995-11-14 | 1999-11-30 | Centre National D'etudes Spatiales | Global space radiopositioning and radionavigation system, beacon and receiver used in this system |
| CN102338873A (en) * | 2011-09-28 | 2012-02-01 | 中国电子科技集团公司第十研究所 | Method for integrally telemetering and ranging target range aircraft |
| CN107994920A (en) * | 2017-11-22 | 2018-05-04 | 南京理工大学 | A kind of cube Satellite TT answering machine and its coherent signal retransmission method |
| CN108134625A (en) * | 2017-12-11 | 2018-06-08 | 北京无线电计量测试研究所 | A kind of two-way satellite time and frequency transfer method |
| CN108845338A (en) * | 2018-07-26 | 2018-11-20 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | Star ground united carrier smoothing pseudo range distance measuring method |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112540388A (en) * | 2020-11-24 | 2021-03-23 | 湖北三江航天险峰电子信息有限公司 | Satellite communication module and uplink signal Doppler compensation method thereof |
| CN112540388B (en) * | 2020-11-24 | 2024-03-22 | 湖北三江航天险峰电子信息有限公司 | Satellite communication module and uplink signal Doppler compensation method thereof |
| CN113507323A (en) * | 2021-06-17 | 2021-10-15 | 西安空间无线电技术研究所 | Inter-satellite frequency transmission system and method based on active phase noise compensation |
| CN114785651A (en) * | 2022-06-21 | 2022-07-22 | 中国人民解放军国防科技大学 | Doppler frequency shift elimination method and system for bidirectional frequency transmission |
| CN114785651B (en) * | 2022-06-21 | 2022-08-26 | 中国人民解放军国防科技大学 | Doppler frequency shift elimination method and system for bidirectional frequency transmission |
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