CN110299952A - A kind of series connection receives corrective network and bearing calibration - Google Patents
A kind of series connection receives corrective network and bearing calibration Download PDFInfo
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- CN110299952A CN110299952A CN201910463210.7A CN201910463210A CN110299952A CN 110299952 A CN110299952 A CN 110299952A CN 201910463210 A CN201910463210 A CN 201910463210A CN 110299952 A CN110299952 A CN 110299952A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/20—Monitoring; Testing of receivers
- H04B17/21—Monitoring; Testing of receivers for calibration; for correcting measurements
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Abstract
The present invention relates to microwave signal process field, spy is related to a kind of series connection and receives corrective network and bearing calibration.Reception corrective network of the invention takes series system to connect, and acquires the signal by A/D module and calculates phase and amplitude offset, to carry out the correction of amplitude and phase to receiving channel.Method of the invention has many advantages, such as that cheap, installation is simple, light-weight, precision is high.
Description
Technical field
The present invention relates to microwave signal process field, spy is related to a kind of series connection and receives corrective network and bearing calibration.
Background technique
In microwave signal receiving channel include height put, be mixed, in put, the analog devices such as A/D chip, different receiving channels
Due to manufacturing process or the difference of electric property, inevitably deposit difference characteristically, bring the response of each channel amplitude and
When the difference of the inconsistency of phase response, each channel amplitude response and phase response will cause follow-up signal processing, to pair
Valve, which is offseted, has larger impact with digital beam froming (DBF) performance, and precision is lower, and then influences the extraction to target in signal.
It is existing to different receiving channel phases and amplitude correction device are as follows: during fabrication, correction module generate 1 road sign quasi wave
Shape generates multidiameter delay waveform by power splitter, and gives multiple corrective networks respectively, the signal point of multiple corrective network outputs
Multipath reception channel is not given, and the signal of multipath reception channel output gives multichannel A/D module respectively, should by A/D module acquisition
Signal simultaneously calculates phase and amplitude offset, to carry out the correction of amplitude and phase to receiving channel.But for hundreds of
Even for thousands of a receiving channels, complicated power splitter is needed, needs very large space not only to install power splitter, Er Qiexu
Hundreds and thousands of isometric cables are wanted to connect power splitter and corrective network, and in order to ensure different receiving channel received signals
Unanimously, it needs on the basis of longest, causes the route length of each branch, decaying big, at high cost.Power splitter and cable price
It is high, and installation power splitter, connecting cable take time and effort.It is therefore desirable to propose a kind of cheap, simple multi-pass of installation
Channel correction device, in order to engineer application.And existing branch off attenuation is big, is unsuitable for cascade compensation, which prevent abilities
The innovation of domain personnel.
Summary of the invention
In view of the deficiencies of the prior art, the present invention provides a kind of series connection to receive corrective network and bearing calibration.
Corrective network of the invention takes series system to connect, and acquires the signal by A/D module and calculates phase and amplitude
Offset, to carry out the correction of amplitude and phase to receiving channel.Method of the invention have cheap, installation is simple,
Light-weight, the advantages that precision is high.
The technical scheme is that the present invention generates 1 road sign waveform by correction module, and give the 1st grade of correction
Network, the signal of the 1st grade of corrective network output give the 2nd grade of corrective network, and the signal of the 2nd grade of corrective network output gives the 3rd
The signal of grade corrective network ... ..., the output of N-1 grades of corrective networks gives N grades of corrective networks.N number of corrective network output
Signal gives the road N receiving channel respectively, and the signal of the road N receiving channel output is given the road N A/D module respectively, acquired by A/D module
The signal simultaneously calculates phase and amplitude offset, to carry out the correction of amplitude and phase to receiving channel.
The beneficial effects of the present invention are: (1) corrective networks at different levels are adopted and are connected serially, the signal amplitude of rear class can subtract
It is small, rear class receiving channel is protected, invisible increases the service life of equipment, by the way of previous parallel connection, receives logical
It road and its is easily damaged.And after using the device of the invention, the reliability of first receiving channel as the mode of parallel connection,
During the work time, reliability greatly improves, and greatly reduces maintenance of equipment cost for his receiving channel.(2) it in the present invention, adopts
It is corrected with concatenated mode, adjacent correction network independent design, cable connection can be very short, or even only needs connector i.e.
Can, decay very little in this way, that is, reduces costs, also ensure that and can connect multistage corrective network.(3) it is a large amount of installation is not needed
Power splitter and function divide cable, reduce fitter's work amount.(4) it does not need that a large amount of power splitter is installed and function divides cable, save
About a large amount of space and manufacturing cost.(5) it does not need that a large amount of power splitter is installed and function divides cable, alleviate weight of equipment.
Detailed description of the invention
Fig. 1 is hardware block diagram；
Fig. 2 is A/D module number enhanced processing figure；
Fig. 3 is A/D module Digital Down Convert processing figure；
Fig. 4 is correction front and back waveform diagram.
Specific embodiment
Explanation of nouns: NCO (Numerically Controlled Oscillator), as coherent oscillator: because two
The formation of a orthogonal coherent oscillator signal with to be multiplied all be digital operation as a result, so its orthogonality can guarantee completely
, as long as guaranteeing operational precision.
Below in conjunction with attached drawing, the present invention is described further.
As described in Figure 1, series connection of the invention receives corrective network, including correction module, N number of corrective network, it is N number of receive it is logical
Road, N number of A/D module, N are natural number, and N is more than or equal to 2.Correction module is connected with the 1st grade of corrective network input port, N grades of correction nets
Network is cascaded, i.e. the signal of the 1st grade of corrective network output gives the 2nd grade of corrective network, the letter of the 2nd grade of corrective network output
3rd level corrective network ... ... number is given, the signal of N-1 grades of corrective networks output gives N grades of corrective networks.Each school
Positive network delivery outlet is connected respectively receiving channel input port, and receiving channel delivery outlet is correspondingly connected with A/D module, each reception
Channel includes phase shifter, attenuator, and A/D module acquires corresponding receiving channel signal, and A/D module output and corresponding phase shifter decline
Subtract device connection.
Correction module generates reference waveform: when receiving correction timing, such as correction module generates the sinusoidal waveform S of 10us
(t) (length of sine wave can be set according to actual needs), and export to corrective network 1.
Corrective network of the invention is by way of strip line is coupled to strip line, by four layers of micro-strip printed board, five layers
Copper foil and four layers of prepreg are process.Each corrective network takes series system to connect, the output end point of each corrective network
The input terminal of each receiving channel is not connected.
The course of work of hardware system of the present invention is:
The correction of receiving channel 1: correction module generates reference waveform (such as sine wave), corrected network 1, receiving channel
It is acquired after 1 by A/D module 1, the data of acquisition is amplified in A/D module 1, calculation process and phase and amplitude is obtained and misses
Difference, is arranged phase shifter corrected value according to phase error, and attenuator corrected value is arranged according to amplitude error value, to realize to the
1 receiving channel automatically corrects.
The correction of receiving channel 2: correction module generates reference waveform (such as sine wave), corrected network 1, corrective network
2, by the acquisition of A/D module 2 (amplitude is less than the signal value that A/D module 1 acquires) after receiving channel 2, to the number of acquisition in A/D module 2
According to amplifying, calculation process and obtaining phase and range error, phase shifter corrected value is arranged according to phase error, according to width
It spends error amount and attenuator corrected value is set, the 2nd receiving channel is automatically corrected to realize.
The correction of receiving channel 3: correction module generates reference waveform (such as sine wave), corrected network 1, corrective network
2, by the acquisition of A/D module 3 (amplitude is less than the signal value that A/D module 2 acquires) after corrective network 3, receiving channel 3, in A/D module 3
The data of acquisition are amplified, calculation process and obtain phase and range error, phase shifter school is arranged according to phase error
Positive value is arranged attenuator corrected value according to amplitude error value, automatically corrects to realize to the 3rd receiving channel.
And so on, the correction of receiving channel N: correction module generates reference waveform (such as sine wave), corrected network
1, corrective network 2, corrective network 3 ..., by A/D module N acquisition, (amplitude is less than A/D module after corrective network N, receiving channel N
N-1 acquisition signal value), the data of acquisition are amplified in A/D module N, calculation process and obtain phase and amplitude mistake
Difference, is arranged phase shifter corrected value according to phase error, and attenuator corrected value is arranged according to amplitude error value, to realize to the
N number of receiving channel automatically corrects.
The invention also discloses the bearing calibration that a kind of series connection receives corrective network, corrective network is connected in series, and corrects net
Network delivery outlet is connect with receiving channel input port, and after correction module sends correction signal, each receiving channel is received
Phasing and reception amplitude correction, test the amplitude attenuation value of each corrective network, such as corrective network 1 to corrective network N
Amplitude attenuation value is respectively A1To AN；The amplification coefficient of each A/D module is determined according to the amplitude attenuation value of corrective network.
Receiving phase correction course are as follows: generate sinusoidal waveform S (the t) (length of sine wave of 10us by correction module first
Can be set according to actual needs), all receiving channels are opened simultaneously (for can walking without this for not channel switch
Suddenly), each road A/D module acquires sinusoidal waveform S (t) signal.A/D module amplifies the signal of acquisition.A/D module to signal into
Row amplification reason and requirement are as follows: since the corrective network series that the signal of each A/D module acquisition passes through is inconsistent, so A/D module 1
To A/D module N, the signal amplitude of acquisition is sequentially reduced, because the amplitude difference is not that receiving channel causes, each A/D module
It needs to carry out digital enhanced processing to the signal of acquisition according to the amplitude attenuation value of corrective networks at different levels, such as the amplification of A/D module 3
Coefficient isThen Digital Down Convert processing is carried out, Digital Down Convert handles to obtain I branch, Q finger values,
Due toFind out the reception amount of phase shift in each channelAltogether
It, takes the average value of intermediate 80 amount of phase shift at 100 points (100 points=10MHz*10us), then converts thereof into six dataThen, corresponding phase shifter (phase shifters' digit of this paper is 6) is set, completes to receive phase
Bit correction restores to work normally timing finally, exiting correction timing.
Receive amplitude correction process are as follows: generate sinusoidal waveform S (the t) (length of sine wave of 10us by correction module first
Can be set according to actual needs), all receiving channels are opened simultaneously (for can walking without this for not channel switch
Suddenly), each road A/D module acquires sinusoidal waveform S (t) signal.A/D module amplifies the signal of acquisition.A/D module to signal into
Row amplification reason and requirement are as follows: since the corrective network series that the signal of each A/D module acquisition passes through is inconsistent, so A/D module 1
To A/D module N, the signal amplitude of acquisition is sequentially reduced, because the amplitude difference is not that receiving channel causes, each A/D module
It needs to carry out digital enhanced processing to the signal of acquisition according to the amplitude attenuation value of corrective networks at different levels, such as the amplification of A/D module 3
Coefficient isThen Digital Down Convert processing is carried out, Digital Down Convert is handled to obtain I branch, Q finger values, be asked
The reception amplitude amount in each channel outTotally 100 points (100 points=
10MHz*10us), the average value of intermediate 80 amplitude amounts is taken, then, corresponding attenuator is arranged, and (the attenuator digit of this paper is
6, wherein 16 be maximum attenuation amount be 16dB), it completes to receive amplitude correction, finally, correction timing is exited, when restoring to work normally
Sequence.
After the completion of receiving phase correction or reception amplitude correction, A/D module is arranged phase shifter according to phase error and corrects
Value is arranged attenuator corrected value according to amplitude error value, automatically corrects to realize to N number of receiving channel.
Digital enhanced processing mode of the invention are as follows: this system is realized at digital amplification using on-line loaded magnified method
Reason.
Because the signal of each A/D module acquisition passes through different corrective network series, the amplification system that each A/D module uses
Number is different, and in order to consider the versatility of program, amplification coefficients at different levels are summarized, and forms a file, by this document programming
Into the FLASH of each A/D module.After A/D module powers on, FPGA reads different coefficient value M according to itself ID number.It is by this
M is counted multiplied by the signal amplitude of acquisition.(such as the signal amplitude that A/D module 1 acquires is 2.2V, the signal amplitude that A/D module 2 acquires
The signal amplitude acquired for 2V, A/D module 3 is 1.82V.Then A/D module 1 need to multiplied by coefficient 1, A/D module 2 need to multiplied by coefficient 1.1,
A/D module 3 need to be multiplied by coefficient 1.21.)
Digital enhanced processing functional block diagram is as shown in Fig. 2, ID number is that radar gives A/D module, the ID of each A/D module in figure
Number different, M is the coefficient read.
Digital Down Convert processing mode of the invention are as follows: this system is realized that number is lower using digital mixing low pass filtering method and become
Frequency is handled.
It can be 10MHZ or more that this system, which requires the sample rate of A/D transformation, and selection is selected according to receiving channel bandwidth,
The centre frequency for inputting intermediate-freuqncy signal is the centre frequency of receiving channel, and NCO selects the negative value of centre frequency.Such as the present embodiment
The sample rate f of middle A/D transformationS=200MHz, input IF signal frequency are 50MHz, and final output data rate is 1 tunnel
The narrowband I branch and Q branch of 10Msps.
Digital Down Convert handles specific steps in the present invention are as follows: first by the local oscillation signal and A/D of the NCO -50MHz generated
Intermediate-freuqncy signal after transformation carries out digital mixing, then carries out low-pass filtering, 2 times of data pick-up, then carries out low pass filtered
The narrowband I/Q data of wave, 10 times of data pick-up output 10Msps.
Digital Down Convert functional block diagram is as shown in figure 3, f in figure0=50MHz,
The wherein analog intermediate frequency real signal that correction module generates are as follows:
A (t) is the amplitude of signal in formula；f0For the centre frequency of intermediate-freuqncy signal；For the phase of signal；The band of signal
Width is B.
In formulaThe referred to as complex envelope of signal can be denoted as
In formula, xI(t) and xQ(t) be referred to as the I branch and Q branch of complex envelope, exactly digital frequency conversion obtain two
A mutually orthogonal component.
Above branch (abbreviation I branch) multiplier output signal is shown in Fig. 3
Low-pass filtered device (LPF) obtains I branch afterwards:
And lower branch (abbreviation Q branch) multiplier output signal is
Low-pass filtered device (LPF) obtains Q branch afterwards:
The comparison of waveform first corrects as shown in figure 4, waveform phase and amplitude is all different before correcting before and after correction of the invention
Then phase corrects amplitude again.It when specific operation, can also first correct amplitude, post-equalization phase.
Series connection of the invention receives corrective network and bearing calibration, can apply in multi-pass such as weather radar, shipborne radars
The phased-array radar field in road, it is light-weight, can be convenient installation, save space and cost using means for correcting of the invention,
When high-precision signal being needed to handle, the correction of amplitude and phase is periodically carried out to channel, such as system is carried out certainly every few minutes
Dynamic correction, can real-time perfoming system compensation, can be overcome in this way by physics such as temperature, humidity, air pressures because to device channels
Influence, keep the microwave system phase and amplitude precision using this method very high, specific precision and phase shifter and attenuator
Digit is related, and if phase shifter is 8, then phase accuracy is reachableDegree, if attenuator is 8, maximum attenuation 16dB, then
Amplitude precision is reachableThose skilled in the art by engine request, can then design phase and the amplitude correction system of different accuracy
System.In the present invention, corrective network unconfined can not connect, therefore, to assure that the last one receiving channel can effectively extract letter
Number.
Claims (6)
1. a kind of series connection receives corrective network, including correction module, N number of corrective network, N number of receiving channel, N number of A/D module, school
Positive module is connected with the 1st grade of corrective network input port, it is characterised in that: N grades of corrective networks are cascaded, each correction net
Network delivery outlet is connected respectively receiving channel input port, and receiving channel delivery outlet is correspondingly connected with A/D module, each receiving channel
Including phase shifter, attenuator, A/D module acquires corresponding receiving channel signal, and A/D module exports and corresponding phase shifter, attenuator
Connection, N are the natural number more than or equal to 2.
2. a kind of series connection according to claim 1 receives corrective network, it is characterised in that: corrective network is strip line coupling
To the form of strip line.
3. a kind of series connection receives the bearing calibration of corrective network, corrective network is received using series connection described in claim 1, it is special
Sign is: testing the amplitude attenuation value of each corrective network, determines each A/D module according to the amplitude attenuation value of corrective network
Amplification coefficient；Receiving phase correction course are as follows: waveform, the road N A/D module acquisition correction signal are generated by correction module；According to each
The amplification coefficient of A/D module amplifies the signal of acquisition, then carries out Digital Down Convert processing, and Digital Down Convert is handled
To I branch, Q finger values, the reception amount of phase shift in each channel is found out, corresponding phase shifter correction is set according to amount of phase shift data are received
Value；Receive amplitude correction process are as follows: waveform, the road N A/D module acquisition correction signal are generated by correction module；According to each A/D module
Amplification coefficient the signal of acquisition is amplified, then carry out Digital Down Convert processing, Digital Down Convert handles to obtain I branch
Road, Q finger values find out the reception amplitude amount in each channel, corresponding attenuator corrected value are arranged according to width metric data is received, N is
Natural number more than or equal to 2.
4. the bearing calibration that a kind of series connection according to claim 3 receives corrective network, it is characterised in that: A/D module is put
Big coefficient isAiFor the amplitude attenuation value of corrective network i, wherein i is expressed as i-th of corrective network.
5. the bearing calibration that a kind of series connection according to claim 3 receives corrective network, it is characterised in that: by each A/D module
Amplification coefficient programming is into the FLASH of each A/D module；After A/D module powers on, FPGA is read and different is according to itself ID number
Numerical value M.
6. the bearing calibration that a kind of series connection according to claim 3 receives corrective network, it is characterised in that: correction module produces
Raw waveform is sine wave.
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| CN2018112140843 | 2018-10-18 | ||
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| CN101145860A (en) * | 2007-07-06 | 2008-03-19 | 哈尔滨工程大学 | Device for real time correction of channel phase amplitude |
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| CN106936522A (en) * | 2017-02-13 | 2017-07-07 | 京信通信技术(广州)有限公司 | A kind of intelligent antenna channel calibration method and calibrating installation |
| EP3291466A1 (en) * | 2016-09-02 | 2018-03-07 | Vestel Elektronik Sanayi ve Ticaret A.S. | Electronic device and method |
| CN107809293A (en) * | 2017-10-09 | 2018-03-16 | 武汉滨湖电子有限责任公司 | A kind of receiving channel multichannel phase and amplitude correction device and bearing calibration |
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2019
- 2019-05-30 CN CN201910463210.7A patent/CN110299952A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101145860A (en) * | 2007-07-06 | 2008-03-19 | 哈尔滨工程大学 | Device for real time correction of channel phase amplitude |
| US20110159831A1 (en) * | 2009-12-28 | 2011-06-30 | Stmicroelectronics (Beijing) R&D Co., Ltd. | Channel estimation for communication systems with multiple transmit antennas |
| EP3291466A1 (en) * | 2016-09-02 | 2018-03-07 | Vestel Elektronik Sanayi ve Ticaret A.S. | Electronic device and method |
| CN106936522A (en) * | 2017-02-13 | 2017-07-07 | 京信通信技术(广州)有限公司 | A kind of intelligent antenna channel calibration method and calibrating installation |
| CN107809293A (en) * | 2017-10-09 | 2018-03-16 | 武汉滨湖电子有限责任公司 | A kind of receiving channel multichannel phase and amplitude correction device and bearing calibration |
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Effective date of registration: 20200612 Address after: 51 No. 430205 Hubei province Wuhan City Liufang high tech Development Zone East Lake Road Applicant after: WUHAN BINHU ELECTRONIC Co.,Ltd. Address before: No. 103-2, Hong Kong Road, Jiang'an District, Wuhan City, Hubei Province Applicant before: Xu Huamin |
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Application publication date: 20191001 |