CN103199914A - Frequency shift repeater based on frequency difference digital compensation and frequency difference digital compensation method - Google Patents
Frequency shift repeater based on frequency difference digital compensation and frequency difference digital compensation method Download PDFInfo
- Publication number
- CN103199914A CN103199914A CN2012102231571A CN201210223157A CN103199914A CN 103199914 A CN103199914 A CN 103199914A CN 2012102231571 A CN2012102231571 A CN 2012102231571A CN 201210223157 A CN201210223157 A CN 201210223157A CN 103199914 A CN103199914 A CN 103199914A
- Authority
- CN
- China
- Prior art keywords
- frequency
- difference
- signal
- remote termination
- circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Abstract
The invention provides a frequency shift repeater based on frequency difference digital compensation and a frequency difference digital compensation method. The frequency shift repeater comprises a near-end machine and a far-end machine, wherein the near-end machine inserts a reference signal of a single frequency into a relay frequency band of a downlink signal, the far-end machine is connected with the near-end machine in a communication mode, the far-end machine comprises a frequency deviation detecting circuit and a far-end frequency compensation circuit, the frequency deviation detecting circuit receives the downlink signal and is used for detecting a frequency difference value between the reference signal in the downlink signal and a local oscillator signal of the far-end machine, and the far-end frequency compensation circuit is used for conducting frequency compensation to an uplink signal and the downlink signal of the far-end machine according to the frequency difference value. The reference signal is inserted into the relay frequency band of the downlink signal by the near-end machine, the far-end machine detects the frequency difference value between the reference signal and the local oscillator signal of the far-end machine and conducts the frequency difference compensation to the uplink signal and the downlink signal according to the frequency difference value, and therefore frequency of the near-end machine and frequency of the far-end machine are synchronous and the frequency difference between the near-end machine and the far-end machine is eliminated.
Description
Technical field
The present invention relates to the frequency-shift repeater field, particularly a kind of frequency-shift repeater and frequency difference digital compensation method based on the frequency difference digital compensation.
Background technology
In frequency-shift repeater, near-end and far-end cause making that the radio-frequency (RF) local oscillator of the two has frequency departure owing to have deviation between the frequency of its crystal oscillator separately, thereby make service signal produce frequency displacement through behind the frequency-shift repeater.According to+/-the crystal oscillator frequency deviation of 2.5ppm calculates, and in the 900M frequency range, frequency departure is+/-2250Hz.This frequency departure (being frequency difference) can have a strong impact on the receptivity of mobile phone and base station.
Usually adopt following method to solve the big problem of frequency departure in the prior art.
(1) crystal oscillator of near-end and far-end adopts the homology reference signal, to eliminate nearly far-end local oscillator frequency difference.Yet in the environment of shift frequency practical application, nearly far-end wide apart can not accomplish to adopt same source reference.
(2) near-end and far-end all adopt high stability crystal oscillator, to reduce frequency difference, make frequency difference control in allowed band.But high stability crystal oscillator is very expensive, and cost is too high, has increased the cost of frequency-shift repeater greatly, and high stability crystal oscillator is easily aging, and the operating time has been grown frequency deviation and also can become big.
Summary of the invention
The invention provides a kind of frequency-shift repeater based on the frequency difference digital compensation and frequency difference digital compensation method, there to be the problem of frequency difference in the solution prior art between near-end and the far-end.
For addressing the above problem, as first aspect of the present invention, provide a kind of frequency-shift repeater based on the frequency difference digital compensation, comprising: near-end machine, near-end machine insert the reference signal of single-frequency to the relaying frequency range of its downstream signal; And remote termination, being connected with the communication of near-end machine, remote termination comprises: the frequency deviation testing circuit receives downstream signal, for detection of the frequency-splitting between the local oscillation signal of the reference signal in the downstream signal and remote termination; And the far-end frequency compensated circuit, be used for according to frequency-splitting upward signal and the downstream signal of remote termination being carried out frequency compensation.
Further, the corresponding frequency word of frequency-splitting is the first frequency word, and the corresponding frequency word of reference signal is the second frequency word, first frequency word and second frequency word and be the 3rd frequency word; Remote termination comprises that also the difference on the frequency coefficient produces circuit, is connected with the far-end frequency compensated circuit with the frequency deviation testing circuit, is used for sending to the far-end frequency compensated circuit according to the ratio generated frequency difference coefficient of first frequency word and the 3rd frequency word and with the difference on the frequency coefficient.
Further, the far-end frequency compensated circuit comprises the intermediate frequency compensating circuit, receives the difference on the frequency coefficient that produces circuit from the difference on the frequency coefficient, is used for according to the difference on the frequency coefficient up intermediate frequency output signal and the descending intermediate frequency input signal of remote termination being carried out the frequency difference compensation.
Further, remote termination also comprises VCXO, and the intermediate frequency compensating circuit is connected with VCXO, and the intermediate frequency compensating circuit is controlled the voltage of VCXO with the frequency of control VCXO according to the difference on the frequency coefficient.
Further, the far-end frequency compensated circuit comprises the RF compensation circuit, receives the difference on the frequency coefficient that produces circuit from the difference on the frequency coefficient, is used for according to the difference on the frequency coefficient up radio-frequency input signals and the downlink radio frequency output signal of remote termination being carried out the frequency difference compensation.
Further, remote termination also comprises VCXO, and the RF compensation circuit is connected with VCXO, and the RF compensation circuit is controlled the voltage of VCXO with the frequency of control VCXO according to the difference on the frequency coefficient.
Further, the near-end machine comprises fixedly crystal oscillator.
As second aspect of the present invention, a kind of frequency difference digital compensation method is provided, comprising: the near-end machine inserts in the service signal has the reference signal of single-frequency, and sends service signal; Remote termination receives service signal, and detects the frequency-splitting between the local oscillation signal of reference signal and remote termination in the service signal that receives, and remote termination carries out frequency difference according to frequency-splitting to its input signal and output signal and compensates.
Further, remote termination obtains the difference on the frequency coefficient according to following formula:
FDF＝-DIF_REF_FW/(REF_FREQ_FW0+DIF_REF_FW)
Wherein, FDF is the difference on the frequency coefficient; DIF_REF_FW is that frequency-splitting is at the corresponding first frequency word in the sample frequency territory of remote termination; REF_FREQ_FW0 is corresponding 32 the second frequency word of the frequency of reference signal.
Further, remote termination carries out the frequency difference compensation according to the difference on the frequency coefficient to the intermediate-freuqncy signal in input signal and the output signal and radiofrequency signal.
The present invention inserts reference signal to its downstream signal in the relaying frequency range at the near-end machine, frequency-splitting between the local oscillation signal of its remote termination reference signal detection and remote termination, according to frequency-splitting the uplink and downlink signal is carried out the frequency difference compensation again, thereby make the Frequency Synchronization of near-end machine and remote termination, to eliminate the frequency difference between the two.
Description of drawings
Fig. 1 schematically shows structural representation of the present invention.
Embodiment
Below in conjunction with accompanying drawing embodiments of the invention are elaborated, but the multitude of different ways that the present invention can be defined by the claims and cover is implemented.
As a first aspect of the present invention, provide a kind of frequency-shift repeater based on the frequency difference digital compensation.As shown in Figure 1, the frequency-shift repeater based on the frequency difference digital compensation among the present invention comprises: near-end machine, near-end machine insert the reference signal of single-frequency to the relaying frequency range of its downstream signal; And remote termination, be connected with the communication of near-end machine.Preferably, the near-end machine comprises fixedly crystal oscillator.
Wherein, remote termination comprises: the frequency deviation testing circuit receives downstream signal, for detection of the frequency-splitting between the local oscillation signal of the reference signal in the downstream signal and remote termination; And the far-end frequency compensated circuit, be used for according to frequency-splitting upward signal and the downstream signal of remote termination being carried out frequency compensation.
As shown in Figure 1, the frequency of reference signal is f0 (this frequency is for agreement or known), and it is the local oscillation signal of f0 ' that remote termination produces corresponding with f0 a, frequency.By the frequency deviation testing circuit, the frequency-splitting that can detect between the two is Δ f.Then, the far-end frequency compensated circuit is according to the value of Δ f, and remote termination carries out frequency compensation, so that the Frequency Synchronization of near-end machine and remote termination.
The present invention inserts the beacon signal of a single-frequency as reference signal to its downstream signal in relaying frequency range (for example center of relaying frequency range) at the near-end machine.Remote termination then detects this reference signal, and detects the frequency-splitting (being frequency difference) between the local oscillation signal of this reference signal and remote termination, thereby detects the side-play amount of frequency.Then, remote termination just can be converted out the frequency difference of uplink and downlink signal demand compensation according to this side-play amount, thereby makes the Frequency Synchronization of near-end machine and remote termination, to eliminate the frequency difference between the two.
Preferably, the corresponding frequency word of frequency-splitting is the first frequency word, and the corresponding frequency word of reference signal is the second frequency word, first frequency word and second frequency word and be the 3rd frequency word; Remote termination comprises that also the difference on the frequency coefficient produces circuit, is connected with the far-end frequency compensated circuit with the frequency deviation testing circuit, is used for sending to the far-end frequency compensated circuit according to the ratio generated frequency difference coefficient of first frequency word and the 3rd frequency word and with the difference on the frequency coefficient.
Further, establishing the corresponding frequency word of frequency-splitting Δ f is the first frequency word, represents with DIF_REF_FW.
The frequency of the reference signal of the downstream signal of known near-end machine is REF_FREQ0, and the nominal sample frequency of near-end machine is FS0.Then corresponding 32 the second frequency word REF_FREQ_FW0 of the frequency of reference signal is:
REF_FREQ_FW0=REF_FREQ0*2^32/FS0 formula (1)
The frequency zero deflection of near-end machine, the difference on the frequency coefficient of establishing remote termination are FDF (ppm of unit), and then the nominal reference frequency REF_FREQ of the descending reception of remote termination is:
REF_FREQ=REF_FREQ0* (1+FDF) formula (2)
Further, detected frequency-splitting DIF_REF (being Δ f) is:
DIF_REF=REF_FREQ0-REF_FREQ=-REF_FREQ0*FDF formula (3)
If the far-end sample frequency is FS0* (1+FDF), when DIF_REF being converted far-end sample frequency territory so, its corresponding first frequency word DIF_REF_FW is:
DIF_REF_FW＝DIF_REF*2^32/(FS0*(1+FDF))
=REF_FREQ_FW0/ (1+FDF)-REF_FREQ_FW0 formula (4)
Then can obtain difference on the frequency coefficient FDF according to formula (4) is:
FDF=-DIF_REF_FW/ (REF_FREQ_FW0+DIF_REF_FW) formula (5)
By formula (5) as can be known, the ratio by first frequency word DIF_REF_FW and the 3rd frequency word (being REF_FREQ_FW0+DIF_REF_FW) just can obtain difference on the frequency coefficient FDF.
Preferably, the far-end frequency compensated circuit comprises the intermediate frequency compensating circuit, receives the difference on the frequency coefficient that produces circuit from the difference on the frequency coefficient, is used for according to the difference on the frequency coefficient up intermediate frequency output signal and the descending intermediate frequency input signal of remote termination being carried out the frequency difference compensation.Please refer to Fig. 1, preferably, remote termination also comprises VCXO, and the intermediate frequency compensating circuit is connected with VCXO NCO, and the intermediate frequency compensating circuit is controlled the voltage of VCXO with the frequency of control VCXO according to the difference on the frequency coefficient.
Embodiment 1:
When descending intermediate frequency input signal was compensated, the frequency of setting capable intermediate frequency input signal was NFD_FREQ0, and its frequency conversion compensating frequency DIF_DN_IN_FREQ is:
DIF_DN_IN_FREQ＝NFD_FREQ0*FDF＝-NFD_FREQ0/REF_FREQ0*DIF_REF
Formula (6)
32 bit frequency words of frequency conversion compensating frequency correspondence are:
DIF_DN_IN_FREQ_FW=-NFD_FREQ0/REF_FREQ0*DIF_REF_FW formula (7)
Embodiment 2:
When up intermediate frequency output signal was compensated, establishing up intermediate frequency output signal frequency was NFU_FREQ0, and its frequency conversion compensating frequency DIF_UP_OUT_FREQ is:
DIF_UP_OUT_FREQ＝NFU_FREQ0*(-FDF)＝NFU_FREQ0/REF_FREQ0*DIF_REF
Formula (8)
The corresponding 32 bit frequency words of its frequency conversion compensating frequency are:
DIF_UP_OUT_FREQ_FW=NFU_FREQ0/REF_FREQ0*DIF_REF_FW formula (9)
Preferably, remote termination also comprises VCXO, the far-end frequency compensated circuit comprises the RF compensation circuit, receives the difference on the frequency coefficient that produces circuit from the difference on the frequency coefficient, is used for according to the difference on the frequency coefficient up radio-frequency input signals and the downlink radio frequency output signal of remote termination being carried out the frequency difference compensation.Please refer to Fig. 1, preferably, the RF compensation circuit is connected with VCXO NCO, and the RF compensation circuit is controlled the voltage of VCXO with the frequency of control VCXO according to the difference on the frequency coefficient.
Embodiment 3:
When the downlink radio frequency output signal was compensated, setting capable radio frequency output signal frequency was FD_FREQ0, and its frequency conversion compensating frequency DIF_FD_OUT_FREQ is:
DIF_FD_OUT_FREQ＝FD_FREQ0*(-FDF)＝FD_FREQ0/REF_FREQ0*DIF_REF
Formula (10)
32 bit frequency words of its correspondence are:
DIF_FD_OUT_FREQ_FW=FD_FREQ0/REF_FREQ0*DIF_REF_FW formula (11)
Embodiment 4:
When up radio-frequency input signals was compensated, the frequency of up radio-frequency input signals was FU_FREQ0, and its frequency conversion compensating frequency DIF_UP_IN_FREQ is:
DIF_UP_IN_FREQ=FU_FREQ0*FDF=-FU_FREQ0/REF_FREQ0*DIF_REF formula (12)
Be converted into 32 bit frequency words:
DIF_UP_IN_FREQ_FW=-FU_FREQ0/REF_FREQ0*DIF_REF_FW formula (13)
Especially, frequency deviation testing circuit, far-end frequency compensated circuit and difference on the frequency coefficient produce circuit and all adopt FPGA to design, and certainly, also can adopt other Logic Circuit Design.
As a second aspect of the present invention, provide a kind of frequency difference digital compensation method.On the basis of above-mentioned frequency-shift repeater, the frequency difference digital compensation method among the present invention comprises: the near-end machine inserts in the service signal has the reference signal of single-frequency, and sends service signal; Remote termination receives service signal, and detects the frequency-splitting between the local oscillation signal of reference signal and remote termination in the service signal that receives, and remote termination carries out frequency difference according to frequency-splitting to its input signal and output signal and compensates.
Preferably, remote termination obtains the difference on the frequency coefficient according to following formula:
FDF＝-DIF_REF_FW/(REF_FREQ_FW0+DIF_REF_FW)
Wherein, FDF is the difference on the frequency coefficient; DIF_REF_FW is that frequency-splitting is at the corresponding first frequency word in the sample frequency territory of remote termination; REF_FREQ_FW0 is corresponding 32 the second frequency word of the frequency of reference signal.
Further, remote termination carries out the frequency difference compensation according to the difference on the frequency coefficient to the intermediate-freuqncy signal in input signal and the output signal and radiofrequency signal.
The above is the preferred embodiments of the present invention only, is not limited to the present invention, and for a person skilled in the art, the present invention can have various changes and variation.Within the spirit and principles in the present invention all, any modification of doing, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (10)
1. the frequency-shift repeater based on the frequency difference digital compensation is characterized in that, comprising:
Near-end machine, described near-end machine insert the reference signal of single-frequency to the relaying frequency range of its downstream signal; With
Remote termination is connected with the communication of described near-end machine, and described remote termination comprises:
The frequency deviation testing circuit receives described downstream signal, for detection of the frequency-splitting between the local oscillation signal of the described reference signal in the described downstream signal and described remote termination; And
The far-end frequency compensated circuit is used for according to described frequency-splitting upward signal and the downstream signal of described remote termination being carried out frequency compensation.
2. frequency-shift repeater according to claim 1, it is characterized in that, the corresponding frequency word of described frequency-splitting is the first frequency word, and the corresponding frequency word of described reference signal is the second frequency word, described first frequency word and described second frequency word and be the 3rd frequency word;
Described remote termination comprises that also the difference on the frequency coefficient produces circuit, be connected with described far-end frequency compensated circuit with described frequency deviation testing circuit, be used for sending to described far-end frequency compensated circuit according to the ratio generated frequency difference coefficient of described first frequency word and described the 3rd frequency word and with described difference on the frequency coefficient.
3. frequency-shift repeater according to claim 2, it is characterized in that, described far-end frequency compensated circuit comprises the intermediate frequency compensating circuit, reception produces the described difference on the frequency coefficient of circuit from described difference on the frequency coefficient, is used for according to described difference on the frequency coefficient up intermediate frequency output signal and the descending intermediate frequency input signal of described remote termination being carried out the frequency difference compensation.
4. frequency-shift repeater according to claim 3, it is characterized in that, described remote termination also comprises VCXO, described intermediate frequency compensating circuit is connected with described VCXO, and described intermediate frequency compensating circuit is controlled the voltage of described VCXO to control the frequency of described VCXO according to described difference on the frequency coefficient.
5. frequency-shift repeater according to claim 2, it is characterized in that, described far-end frequency compensated circuit comprises the RF compensation circuit, reception is used for according to described difference on the frequency coefficient up radio-frequency input signals and the downlink radio frequency output signal of described remote termination being carried out the frequency difference compensation from the described difference on the frequency coefficient of described difference on the frequency coefficient generation circuit.
6. frequency-shift repeater according to claim 5, it is characterized in that, described remote termination also comprises VCXO, described RF compensation circuit is connected with described VCXO, and described RF compensation circuit is controlled the voltage of described VCXO to control the frequency of described VCXO according to described difference on the frequency coefficient.
7. according to each described frequency-shift repeater among the claim 1-6, it is characterized in that described near-end machine comprises fixedly crystal oscillator.
8. a frequency difference digital compensation method is characterized in that, comprising:
The near-end machine inserts in the service signal has the reference signal of single-frequency, and sends described service signal;
Remote termination receives described service signal, and detecting frequency-splitting between the local oscillation signal of reference signal and described remote termination in the described service signal receive, described remote termination carries out frequency difference according to described frequency-splitting to its input signal and output signal and compensates.
9. frequency difference digital compensation method according to claim 8 is characterized in that, described remote termination obtains the difference on the frequency coefficient according to following formula:
FDF＝-DIF_REF_FW/(REF_FREQ_FW0+DIF_REF_FW)
Wherein, FDF is the difference on the frequency coefficient; DIF_REF_FW is that described frequency-splitting is at the corresponding first frequency word in the sample frequency territory of described remote termination; REF_FREQ_FW0 is corresponding 32 the second frequency word of the frequency of described reference signal.
10. frequency difference digital compensation method according to claim 9 is characterized in that, described remote termination carries out the frequency difference compensation according to described difference on the frequency coefficient to the intermediate-freuqncy signal in described input signal and the described output signal and radiofrequency signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012102231571A CN103199914A (en) | 2012-07-02 | 2012-07-02 | Frequency shift repeater based on frequency difference digital compensation and frequency difference digital compensation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012102231571A CN103199914A (en) | 2012-07-02 | 2012-07-02 | Frequency shift repeater based on frequency difference digital compensation and frequency difference digital compensation method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103199914A true CN103199914A (en) | 2013-07-10 |
Family
ID=48722291
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012102231571A Pending CN103199914A (en) | 2012-07-02 | 2012-07-02 | Frequency shift repeater based on frequency difference digital compensation and frequency difference digital compensation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103199914A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113179395A (en) * | 2021-04-30 | 2021-07-27 | 深圳市金乾象科技有限公司 | Camera remote monitoring video transmission device |
| CN113206682A (en) * | 2021-04-29 | 2021-08-03 | 展讯通信（上海）有限公司 | Near-end combining unit, far-end combining unit and indoor distribution system |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4817197A (en) * | 1986-07-18 | 1989-03-28 | Nippon Telegraph And Telephone Corporation | Mobile communication apparatus |
| CN102025666A (en) * | 2010-12-15 | 2011-04-20 | 中兴通讯股份有限公司 | Method and device for realizing IQ signal correction in base station transmitter equipment |
| CN202713303U (en) * | 2012-06-29 | 2013-01-30 | 深圳格兰泰克科技有限公司 | Frequency shift repeater based on frequency difference digital compensation |
-
2012
- 2012-07-02 CN CN2012102231571A patent/CN103199914A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4817197A (en) * | 1986-07-18 | 1989-03-28 | Nippon Telegraph And Telephone Corporation | Mobile communication apparatus |
| CN102025666A (en) * | 2010-12-15 | 2011-04-20 | 中兴通讯股份有限公司 | Method and device for realizing IQ signal correction in base station transmitter equipment |
| CN202713303U (en) * | 2012-06-29 | 2013-01-30 | 深圳格兰泰克科技有限公司 | Frequency shift repeater based on frequency difference digital compensation |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113206682A (en) * | 2021-04-29 | 2021-08-03 | 展讯通信（上海）有限公司 | Near-end combining unit, far-end combining unit and indoor distribution system |
| CN113206682B (en) * | 2021-04-29 | 2022-09-16 | 展讯通信（上海）有限公司 | Near-end combining unit, far-end combining unit and indoor distribution system |
| CN113179395A (en) * | 2021-04-30 | 2021-07-27 | 深圳市金乾象科技有限公司 | Camera remote monitoring video transmission device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| AU2017333946B2 (en) | Random access method for multiple numerology operation | |
| US8630598B2 (en) | Methods and apparatus for measuring and/or using transmitter and/or receiver IQ imbalance information and/or DC offset information | |
| US9450717B2 (en) | Method for changing TDD uplink and downlink configuration | |
| CN110557207B (en) | Calibrating phased array systems | |
| CN104135296B (en) | Adjustable mean frequency wireless receiver and bluetooth module | |
| US20140369243A1 (en) | Frequency Synchronization Method for Nodes in a Downlink Coordinated Multiple Point Transmission Scenario | |
| JP2008187340A (en) | Radio communication system, base station, and synchronization method | |
| KR101646522B1 (en) | Apparatus and method for frequency offset estimation in mobile communication system | |
| CN105682214B (en) | Baseband and radio frequency combined time sequence adjusting method and device | |
| CN101500248B (en) | Antenna calibration method and apparatus | |
| ZA200906425B (en) | Improvement to synchronization methods for single-frequency simulcast mobile radio communication networks | |
| CN103199914A (en) | Frequency shift repeater based on frequency difference digital compensation and frequency difference digital compensation method | |
| CN100546216C (en) | Obtain the system and the method thereof of reference clock in the frequency-shift repeater | |
| US8483731B2 (en) | Systems and methods for base station reference frequency correction and timing correction using transceiver feedback | |
| CN202713303U (en) | Frequency shift repeater based on frequency difference digital compensation | |
| US10033511B2 (en) | Synchronization of co-located radios in a dynamic time division duplex system for interference mitigation | |
| US20080299972A1 (en) | Method for synchronising a radio communication system, corresponding base station and terminal | |
| CN1988412A (en) | High frequency broad band friquency shift repeator | |
| US20190182025A1 (en) | Base station apparatus and method for controlling base station apparatus | |
| JP5272893B2 (en) | AFC circuit and AFC control method for digital radio | |
| KR100673868B1 (en) | Time division duplex optic repeater which could transmit and receive the data with single wavelength in fiber-optic | |
| JP2017069809A (en) | Communication device | |
| KR100596724B1 (en) | An apparatus and method of synchronization systems for TDD based small-scaled radio frequency repeaters | |
| WO2008021004A2 (en) | Remote monitoring and calibration of system reference clock using network timing reference | |
| JP4763539B2 (en) | Wireless system, wireless transmitter and wireless receiver |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20130710 |