CN101938306A - Inhibition method of uplink base noise of GSM (Global System for Mobile Communication) digital optical fiber repeater station - Google Patents

Inhibition method of uplink base noise of GSM (Global System for Mobile Communication) digital optical fiber repeater station Download PDF

Info

Publication number
CN101938306A
CN101938306A CN200910112642XA CN200910112642A CN101938306A CN 101938306 A CN101938306 A CN 101938306A CN 200910112642X A CN200910112642X A CN 200910112642XA CN 200910112642 A CN200910112642 A CN 200910112642A CN 101938306 A CN101938306 A CN 101938306A
Authority
CN
China
Prior art keywords
noise
thresholding
digital
energy
signal
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.)
Granted
Application number
CN200910112642XA
Other languages
Chinese (zh)
Other versions
CN101938306B (en
Inventor
陈凌宇
石江宏
谢思雄
陈岳林
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xiamen University
Original Assignee
Xiamen University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Xiamen University filed Critical Xiamen University
Priority to CN200910112642XA priority Critical patent/CN101938306B/en
Publication of CN101938306A publication Critical patent/CN101938306A/en
Application granted granted Critical
Publication of CN101938306B publication Critical patent/CN101938306B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02DCLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00Reducing energy consumption in communication networks
    • Y02D30/70Reducing energy consumption in communication networks in wireless communication networks

Abstract

The invention discloses an inhibition method of an uplink base noise of a GSM (Global System for Mobile Communication) digital optical fiber repeater station. In the method, the GSM digital optical fiber repeater station used as a remote machine converts wireless multi-carrier signals to zero intermediate frequency signals, a base noise inhibition module calculates an energy spectrum of each frequency point in the zero intermediate frequency signals by arranging a power calculation and discrimination unit behind a last level decimation filter of each frequency point of a digital down conversion module, and the energy spectrum is compared with a noise opening and closing threshold; when the energy of input signals is smaller than the noise closing threshold, signal output is zero, and if the energy of the input signals is gradually increased and is bigger than a noise opening threshold, the input signals are output without distortion; when the energy of the input signals is reduced and is higher than a noise closing threshold, the input signals are continuously output without distortion until the energy of input signals is smaller than the noise closing threshold, and the signal output is zero. The invention inhibits the base noise in the input signals and can better control the interference of the base noise to a whole system without base noise accumulation when multiple remote machines are cascaded.

Description

The inhibition method of GSM digital optical fiber direct station up link back noise
Technical field
The invention belongs to the multi-carrier wireless communication field,, proposed a kind of inhibition method of back noise, especially be applicable to the inhibition method of GSM digital optical fiber direct station up link back noise especially at the GSM cell mobile communication systems.
Background technology
Along with the develop rapidly of mobile communication cause, people improve constantly the area coverage of cellular mobile communication networks and the requirement of covering quality.Because the transmission feature of wireless signal, inevitably in the urban district or the suburb have coverage hole.And these blind areas are often little owing to scope, and customer volume is also few, adopts the way of newly-built base station to seem that cost is higher in these blind areas.The repeater is with less, simple in structure, the easy for installation advantage such as flexibly of its investment, becomes to remedy the blind area, optimizes the important means of the network coverage.
Up to now, the two-way treatment technology of signal of simulation standard is all adopted in the GSM repeater, because it directly receives, amplifies and retransmit the radiofrequency signal of base station, place and user mobile phone, so the quality of its performance and index also directly influences the quality of mobile communications network.A high-quality repeater can be improved these regional communication qualities effectively, solve problems such as call drop, otherwise unnecessary interference and noise then can be brought to mobile communications network in the inferior repeater of performance, cause call drop or base station obturation, have a strong impact on network quality.
In the wireless communication system, communicating pair can be because factors such as communication distance variation, barrier obstructions, the signal that makes communicating pair receive is less, when the signal strength signal intensity that receives when threshold level fluctuates up and down, when communication will occur and connect, the time and the phenomenon that disconnects has so just been brought unnecessary interference and noise to cordless communication network, have a strong impact on communication quality.
Digital optical fiber direct station can be realized multicarrier, flexile quickly networking mode, supports multiband and open architecture, and this system is made up of the remote termination of a near-end machine and Duo Tai cascade usually.Present applied digital optical fiber direct station remote termination structure as shown in Figure 1a, generally include analog module and digital signal processing module, wherein the analog module comprises that mainly digital to analog converter (DAC), analog to digital converter (ADC), low noise amplifier, multi-carrier power amplifier and analog radio frequency receive, transmitter; This digital signal processing module mainly comprises Digital Down Converter Module, Digital Up Convert module and optical fiber communication (CPRI) interface; Be used for realizing that numeral goes up down-conversion, and optical fiber communication functions such as (CPRI).Fig. 1 b description habit has the structure chart of one of the main modular of digital optical fiber direct station Digital Down Converter Module.When a GSM sub-district that is assigned n carrier frequency frequency, it should have n frequency-selecting passage, and promptly the number of its frequency-selecting passage must be identical with the carrier frequency number that cell allocation arrives.Wherein can dispose the angular frequency w of mixing by the frequency word that disposes each frequency-selecting passage, this can artificially be disposed by engineering staff's means such as man-machine interactive system by equipment when equipment is installed.
Owing to practise in the GSM digital optical fiber repeater system that has and do not have the back noise inhibit feature, like this when many remote termination cascades, in same time slot, each remote termination upstream noise also can superpose at the near-end machine, thereby higher back noise appears, be coupled to the base station by the near-end machine, influence the performance of base station system.
Summary of the invention
The objective of the invention is to propose a kind of inhibition method of GSM digital optical fiber direct station up link back noise, can be effectively according to the feature of each carrier signal in the multi-carrier communications systems, realize noise suppressed by in remote termination, increasing back noise inhibition module, avoid the stack of upstream noise; Open and close the thresholding of two noises simultaneously by setting, avoid frequently switching at the switch that carries out occurring when back noise suppresses.
A kind of inhibition method of GSM digital optical fiber direct station up link back noise mainly comprises following step:
Step 1: the back noise that goes out whole system earlier by apparatus measures, setting is closed the back noise bigger 3dB of thresholding than the whole system of measuring gained as the noise that back noise in the GSM digital high-frequency amplification station of remote termination suppresses module, and sets noise unlatching thresholding and close the high 2dB to 8dB of thresholding than noise;
Step 2, by antenna the wireless multi-carrier signal is coupled into as the GSM digital optical fiber direct station of remote termination, via being transformed into the analog intermediate frequency multi-carrier signal after the processing such as the amplification of radio frequency processing module, mixing, filtering, then it is become digital signal by analog to digital converter; Convert the digital signal of importing to zero intermediate frequency signals through mixing, filtering extraction respectively by Digital Down Converter Module at last, and deliver to back noise and suppress module;
Step 3: this back noise suppresses module by behind each frequency afterbody decimation filter of Digital Down Converter Module power calculation and judgement unit being set, calculate the energy spectrum of each frequency afterbody decimation filter in this zero intermediate frequency signals, and current energy spectrum and noise are opened and closed thresholding compare, when the input signal energy spectrum is closed thresholding less than noise, then signal is output as 0, if the input signal energy increases gradually and when opening thresholding greater than noise, just with the undistorted output of input signal; And when the input signal energy reduces and also is higher than noise and closes thresholding, continue to allow input signal export undistortedly, when the input signal energy was lower than noise and closes thresholding, then signal was output as 0.
The inhibition method of a kind of GSM digital optical fiber direct station of the present invention up link back noise, back noise is set in the GSM digital optical fiber direct station as remote termination suppresses module, comparison by thresholding is closed and opened to input signal and noise suppresses the back noise in the input signal; Like this when many remote termination cascades, in same time slot, thereby back noise stack can not appear in each remote termination upstream noise in the near-end machine produces higher back noise, and be coupled to the base station, and then have influence on the performance of base station system, therefore, the present invention can control the interference of back noise to whole base station system preferably.
Description of drawings
Fig. 1 a is the operation principle block diagram of existing GSM digital optical fiber repeater system;
Fig. 1 b is the operation principle block diagram of the Digital Down Convert of existing GSM digital optical fiber repeater system;
Fig. 2 a is the operation principle block diagram that has increased the GSM digital optical fiber repeater system of back noise inhibition module;
Fig. 2 b is the detailed operation theory diagram after Digital Down Convert has increased back noise inhibition module;
Fig. 3 is the processing procedure schematic diagram of noise elimination thresholding among the present invention.
The invention will be further described below in conjunction with the drawings and specific embodiments.
Embodiment
Shown in Fig. 2 a, the present invention proposes a kind of inhibition method of GSM digital optical fiber direct station up link back noise, with the as close as possible radio frequency of analog to digital converter (ADC) in broadband, realize the various functions of communication system to the full extent by software.
This GSM digital optical fiber direct station can be realized multicarrier, flexile quickly networking mode, supports multiband and open architecture, and this system is made up of the remote termination of a near-end machine and Duo Tai cascade usually.The present invention is directed to this remote termination and carry out the inhibition of back noise.GSM digital optical fiber direct station as remote termination mainly comprises analog module 1 and digital signal processing module 2, and wherein analog module 1 comprises antenna 11, radio frequency processing module 14, analog to digital converter (ADC) 15, digital to analog converter (DAC) 16; This digital signal processing module 2 comprises that Digital Down Convert (DDC) module 21, Digital Up Convert (DUC) module 22, back noise suppress module 23, optical fiber communication module (CPRI) 24 and optical-electrical converter 25.
At first, as the GSM digital optical fiber direct station of remote termination the wireless multi-carrier signal is coupled into radiofrequency signal by antenna 11, radio frequency processing module 14 is finished the conversion between radiofrequency signal and the analog if signal, then convert digital signal to by analog to digital converter (ADC) 15, processing procedures such as digital mixing by Digital Down Convert (DDC) module 21 and filtering extraction become the digital signal of input into zero intermediate frequency signals at last.
If the baseband signal of wireless communication system is through pseudo-random process, and then the power spectral density of this signal size is directly proportional with the energy spectrum of signal, and the energy spectrum of signal then is directly proportional with signal energy in a period of time.So the present invention can obtain the energy of input signal in a period of time, promptly can be equivalent to the power spectral density of input signal.Owing on the Project Realization, generally require the outer inhibition of band of filter to reach 60dBc.Therefore the power spectrum of this input signal mainly concentrates in a certain frequency band range.
As shown in Figure 3, the present invention proposes a kind of method that two noise gates suppress noise that is provided with, one of them opens thresholding for noise, and another closes thresholding for noise.
Close thresholding when the input signal energy less than noise, then output signal is changed to 0, if the input signal energy increases gradually and when opening thresholding greater than noise, just output signal is equaled undistorted output; And when the input signal energy reduces and also is higher than noise and closes thresholding, continue to allow input signal export undistortedly, when the input signal energy is lower than noise and closes thresholding, signal output is changed to 0.
The invention provides a kind of inhibition method of GSM digital optical fiber direct station up link back noise, comprise following step:
Step 1: back noise suppresses the setting of the noise open and close thresholding of module 23
Generally situation about using according to engineering is determined, the gain of general and front radio-frequency module is relevant with the SNR of analog to digital converter 15, and the prime radio-frequency module gains big more, and the back noise of its radio-frequency module is also bigger accordingly.General noise is closed the maximum back noise height of thresholding than radio-frequency module; Noise is opened thresholding and closed the thresholding height than noise in addition, and is concrete relevant with the back noise of system hardware circuit.The present invention sets the noise of back noise inhibition module 23 and closes thresholding than more than the bigger 3dB of the back noise of the measured whole system that obtains by the back noise of apparatus measures whole system, can guarantee that like this circuit noise of system can not disturb the digital processing process; And set noise unlatching thresholding and close the high 2dB to 8dB of thresholding, can avoid frequent switching like this owing to signal than noise, after the signal that causes is blocked, the frequency spectrum diffusion that signal non-linear distortion causes;
Step 2, by antenna 11 the wireless multi-carrier signal is coupled into as the GSM digital optical fiber direct station of remote termination, after amplification by radio frequency processing module 14, mixing, filtering etc. are handled again, be converted into the analog intermediate frequency multi-carrier signal, then it become digital signal by analog to digital converter (ADC) 15; Convert the multi-carrier signal of input to zero intermediate frequency signals through mixing, filtering extraction respectively by Digital Down Converter Module 21 at last, i.e. X0 (n), X1 (n) ..., Xn (n), and deliver to back noise and suppress module 23;
Step 3: shown in Fig. 2 b, this back noise suppresses power calculation and the judgement unit of module 23 by being provided with behind Digital Down Converter Module 21 each frequency afterbody decimation filters, calculate the energy spectrum of each frequency afterbody decimation filter in this zero intermediate frequency signals, and current energy spectrum and noise opening and closing thresholding compared, when the input signal energy spectrum is closed thresholding less than noise, then this input signal is considered as back noise, signal is output as 0, if the input signal energy increases gradually and when opening thresholding greater than noise, with the undistorted output of input signal; And when the input signal energy reduces and is higher than noise and closes thresholding, continue to allow input signal export undistortedly, and when the input signal energy is lower than noise and closes thresholding, then this signal being considered as back noise, signal is output as 0.
The energy spectrum Ex (n) of described input zero intermediate frequency signals Xn (n)=Ix (n) 2+ Qx (n) 2, wherein Ex (n) represents the energy spectrum of input signal Xn (n), Ix (n) expression I road signal, and Qx (n) expression Q road signal, j is used for representing complex signal; In the FPGA implementation procedure, generally can adopt the process of multiply accumulating to calculate above-mentioned energy spectrum.
As shown in Figure 3, described Ex represents the energy spectrum of input signal X (n), and Eoff and Eon represent that respectively noise is closed thresholding and noise is opened thresholding, Disable is that noise suppressing function is not enabled in 1 expression, just output signal X (n) out is equaled input signal X (n), input signal is exported undistortedly; And Disable be 0 the expression enable noise suppressing function, just input signal X (n) is considered as back noise not export, then output signal X (n) out equals 0, also can see the inhibition flow process of back noise from Fig. 2 b.

Claims (1)

1. the inhibition method of a GSM digital optical fiber direct station up link back noise is characterized in that comprising following step:
Step 1: the back noise that goes out whole system earlier by apparatus measures, setting is closed the back noise bigger 3dB of thresholding than the whole system of measuring gained as the noise that back noise in the GSM digital high-frequency amplification station of remote termination suppresses module, and sets noise unlatching thresholding and close the high 2dB to 8dB of thresholding than noise;
Step 2, by antenna the wireless multi-carrier signal is coupled into as the GSM digital optical fiber direct station of remote termination, be transformed into the analog intermediate frequency multi-carrier signal via processing such as the amplification of radio frequency processing module, mixing, filtering, then it become digital signal by analog to digital converter; Convert the digital signal of importing to zero intermediate frequency signals through mixing, filtering extraction respectively by Digital Down Converter Module at last, and deliver to back noise and suppress module;
Step 3: this back noise suppresses power calculation and the judgement unit of module by being provided with behind each frequency afterbody decimation filter of Digital Down Converter Module, calculate the energy spectrum of each frequency afterbody decimation filter in this zero intermediate frequency signals, and current energy spectrum and noise opening and closing thresholding compared, when the input signal energy is closed thresholding less than noise, then signal is output as 0, if the input signal energy increases gradually and when opening thresholding greater than noise, then with the undistorted output of input signal; And when the input signal energy reduces and is higher than noise and closes thresholding, continue to allow input signal export undistortedly, when the input signal energy was lower than noise and closes thresholding, then signal was output as 0.
CN200910112642XA 2009-09-29 2009-09-29 Inhibition method of uplink base noise of GSM (Global System for Mobile Communication) digital optical fiber repeater station Expired - Fee Related CN101938306B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN200910112642XA CN101938306B (en) 2009-09-29 2009-09-29 Inhibition method of uplink base noise of GSM (Global System for Mobile Communication) digital optical fiber repeater station

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN200910112642XA CN101938306B (en) 2009-09-29 2009-09-29 Inhibition method of uplink base noise of GSM (Global System for Mobile Communication) digital optical fiber repeater station

Publications (2)

Publication Number Publication Date
CN101938306A true CN101938306A (en) 2011-01-05
CN101938306B CN101938306B (en) 2013-06-05

Family

ID=43391460

Family Applications (1)

Application Number Title Priority Date Filing Date
CN200910112642XA Expired - Fee Related CN101938306B (en) 2009-09-29 2009-09-29 Inhibition method of uplink base noise of GSM (Global System for Mobile Communication) digital optical fiber repeater station

Country Status (1)

Country Link
CN (1) CN101938306B (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101977426A (en) * 2010-10-26 2011-02-16 三维通信股份有限公司 Method for reducing uplink noise of GSM (Global System for Mobile Communications) digital repeater
CN102170690A (en) * 2011-04-20 2011-08-31 京信通信系统(中国)有限公司 A gain control method of a WCDMA radio remote unit
CN103634250A (en) * 2013-12-16 2014-03-12 深圳国人通信股份有限公司 Method and device for restraining ground noise signal from upraising
CN103957020B (en) * 2014-05-06 2016-08-10 重庆邮电大学 A kind of signal intermediate frequency supporting multi-mode mobile communication system receives device
CN106685867A (en) * 2017-01-22 2017-05-17 东南大学 Upstream noise inhibiting method automatically adapting to noise thresholds in LTE-distributed relay system
CN106850033A (en) * 2017-02-06 2017-06-13 东南大学 Uplink noise suppressing method in LTE distributed relay systems
CN107197471A (en) * 2017-05-25 2017-09-22 京信通信系统(中国)有限公司 A kind of repeater business statistical method and device
CN112615802A (en) * 2020-12-18 2021-04-06 深圳市佳贤通信设备有限公司 Uplink background noise and interference suppression system and method for 5G communication base station

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101409579A (en) * 2008-10-15 2009-04-15 京信通信系统(中国)有限公司 Traffic stream system and method for GSM discharging-directly station

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101409579A (en) * 2008-10-15 2009-04-15 京信通信系统(中国)有限公司 Traffic stream system and method for GSM discharging-directly station

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101977426B (en) * 2010-10-26 2013-07-10 三维通信股份有限公司 Method for reducing uplink noise of GSM (Global System for Mobile Communications) digital repeater
CN101977426A (en) * 2010-10-26 2011-02-16 三维通信股份有限公司 Method for reducing uplink noise of GSM (Global System for Mobile Communications) digital repeater
CN102170690B (en) * 2011-04-20 2014-08-20 京信通信系统(中国)有限公司 A gain control method of a WCDMA radio remote unit
CN102170690A (en) * 2011-04-20 2011-08-31 京信通信系统(中国)有限公司 A gain control method of a WCDMA radio remote unit
CN103634250B (en) * 2013-12-16 2017-04-12 深圳国人通信股份有限公司 Method and device for restraining ground noise signal from upraising
CN103634250A (en) * 2013-12-16 2014-03-12 深圳国人通信股份有限公司 Method and device for restraining ground noise signal from upraising
CN103957020B (en) * 2014-05-06 2016-08-10 重庆邮电大学 A kind of signal intermediate frequency supporting multi-mode mobile communication system receives device
CN106685867A (en) * 2017-01-22 2017-05-17 东南大学 Upstream noise inhibiting method automatically adapting to noise thresholds in LTE-distributed relay system
CN106685867B (en) * 2017-01-22 2020-01-17 东南大学 Uplink noise suppression method with adaptive noise threshold in LTE distributed relay system
CN106850033A (en) * 2017-02-06 2017-06-13 东南大学 Uplink noise suppressing method in LTE distributed relay systems
CN106850033B (en) * 2017-02-06 2020-05-05 东南大学 Uplink noise suppression method in LTE (Long term evolution) distributed relay system
CN107197471A (en) * 2017-05-25 2017-09-22 京信通信系统(中国)有限公司 A kind of repeater business statistical method and device
CN112615802A (en) * 2020-12-18 2021-04-06 深圳市佳贤通信设备有限公司 Uplink background noise and interference suppression system and method for 5G communication base station
CN112615802B (en) * 2020-12-18 2023-04-14 深圳市佳贤通信设备有限公司 Uplink background noise and interference suppression system and method for 5G communication base station

Also Published As

Publication number Publication date
CN101938306B (en) 2013-06-05

Similar Documents

Publication Publication Date Title
CN101938306B (en) Inhibition method of uplink base noise of GSM (Global System for Mobile Communication) digital optical fiber repeater station
CN101453228B (en) Common station address interference elimination system and method
CN101119121B (en) Anti-interference method in receiver, anti-interference receiver and anti-interference device
CN101615958B (en) Method for detecting isolation between antennas for digital radio repeater system
CN101938821B (en) Method for inhibiting uplink back noise of digital optical fiber repeater
CN202085164U (en) Baseband digitalization apparatus for improving efficiency of power amplifier in adaptive ICS repeater
CN101399595A (en) GSM repeater uplink noise suppressing method based on baseband signal processing
CN207442845U (en) A kind of new multiband WiMAX repeater
CN203219304U (en) Energy-efficient multicarrier digital fiber microwave remote extension system
CN202269021U (en) Multi-system access platform for airport communication
CN101547037A (en) GSM digital wireless repeater and method for shutting off time slot of uplink carrier wave
CN109286407B (en) Interference signal suppression device and method for suppressing strong interference signal
CN106850033A (en) Uplink noise suppressing method in LTE distributed relay systems
CN101594710A (en) TD direct end uplink link automatic shut-off method
CN203942528U (en) A kind of wireless coverage strengthens equipment
CN101640950B (en) Variable band width frequency-shift and frequency-selective digital repeater
CN101917220B (en) Repeater for eliminating near-far effect
CN201479134U (en) GSM wireless repeater station with ascending noise inhibition function
KR100758883B1 (en) Digital multiple path signal matching device of repeater
CN202269020U (en) CATV (community antenna television) wireless signal distribution system using frequency conversion technology
CN202713360U (en) Repeater and self excitation interference elimination device thereof
CN201733303U (en) SCDMA outdoor radio frequency amplification device
CN201248034Y (en) Wireless multi-carrier signal suppresser
CN100349389C (en) Communication signal bidirection amplifier
CN201414218Y (en) GSM trunk amplifier with uplink noise suppression function

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20130605

Termination date: 20210929