CN102263595B - Many nets merge Fiber Access System - Google Patents

Abstract

Embodiments provide a kind of many nets and merge Fiber Access System, have larger multifrequency far-end capping unit extended capability for realizing one, the network coverage is wider, covers the multiple networks fusion fibre system that signal is stronger.A kind of many nets merge Fiber Access System, comprise multifrequency near-end unit and multifrequency far-end capping unit, multifrequency near-end unit is for being coupled from the downlink radio-frequency signal of base station, multifrequency far-end capping unit is supplied to provide radio frequency signal to terminal by optical fiber after converting downlink optical signal to, and receive the uplink optical signal that far end device passed over by optical fiber, send to base station to communicate; Multifrequency far-end capping unit is used for converting the downlink radio-frequency signal that multifrequency near-end unit provides to downlink optical signal, for terminal provides wireless communication signals, and receive the upstream radio-frequency signal of self terminal, be supplied to multifrequency near-end unit by optical fiber after upstream radio-frequency signal being converted to uplink optical signal.

Description

Many nets merge Fiber Access System

Technical field

The present invention relates to wireless communication field, particularly relate to a kind of many nets and merge Fiber Access System.

Background technology

Along with the development of cordless communication network, the 2G of multiple types, 3G network needs the indoor and outdoor network coverage simultaneously.

Traditional mobile communication indoor distribution system generally adopts coaxial cable system to carry out networking, but along with the increase of network formats, this type systematic shows more limitation in specific implementation, be mainly reflected in: system master, cable, device and power supply unit One's name is legion, volume weight are larger, cause networking affect wide, great in constructing amount, the construction period is long, meet an urgent need site operable slightly poor; Construction easily causes some to destroy to building, such as, in metope perforation, cable smallpox cabling etc., and exposing cable need be set with pvc pipe, and fitting-up can be allowed to be partially damaged, and makes administrative office, owner to this strong reaction, and acceptance is poor; Whole system complex structure, to take up room, install, dismounting difficulty, maintenance workload is large; Shared by multiple systems design, networking and when safeguarding contradiction more outstanding.

For above situation, relative to traditional coaxial cable connecting system, introduce Fiber Access System, Fiber Access System has that the life-span is long, reliability is high, the advantage of strong interference immunity, optical transport has very strong extended capability, and easily realizes the fusion of multiple standard.

Existing fiber connecting system 1 multifrequency near-end Element Theory can be accomplished expansion 16 multifrequency far-end capping units, but actual open with maintenance process in there will be telephone traffic and concentrate on a certain sector, easily cause traffic congestion and upstream noise problem rambunctious, introduce the noise of LNA and optical device, directly have influence on the receiving sensitivity of base station, reduce the coverage of base station, therefore 4 multifrequency far-end capping units can only be expanded in actual use, expansion number again increase that the up end can be caused to make an uproar is excessive, severe jamming is caused to base station; Secondly, legacy equipment optical signal transmission mostly adopts 1310nm and 1550nm multiplexing transmission, and device cost is higher, multiplexing transmission data stability is low; The light unit of fibre system mostly adopts the mode of 1 receipts 1 in the past again, and extended distal end machine can only adopt light to divide, close the mode on road, and loss of signal great Qie Mei road gain loss is not easy to automatic adjustment.

Summary of the invention

Embodiments provide a kind of many nets and merge Fiber Access System, have larger multifrequency far-end capping unit extended capability for realizing one, the network coverage is wider, covers the multiple networks fusion fibre system that signal is stronger.

Embodiments provide a kind of many nets and merge Fiber Access System, for merging the mobile communications network of multiple types, realize the communication connection between base station and terminal, comprise at least one or more multifrequency far-end capping unit of a multifrequency near-end unit and expansion

Described multifrequency near-end unit is for being coupled from the downlink radio-frequency signal of base station, described multifrequency far-end capping unit is supplied to provide radio frequency signal to terminal by optical fiber after converting downlink optical signal to, and receive the uplink optical signal that described far end device passed over by optical fiber, send to described base station to communicate;

Described multifrequency far-end capping unit is used for converting the downlink radio-frequency signal that described multifrequency near-end unit provides to downlink optical signal, for terminal provides wireless communication signals, and receive the upstream radio-frequency signal of self terminal, be supplied to described multifrequency near-end unit by optical fiber after converting described upstream radio-frequency signal to uplink optical signal.

Preferably, comprise one or more multi-frequency optical TU Trunk Unit further,

Described multi-frequency optical TU Trunk Unit is used for being arranged between described multifrequency near-end unit and described multifrequency far-end capping unit, makes a multifrequency near-end unit easily extensible more multifrequency far-end capping unit.

Preferably, described multifrequency near-end unit comprises:

Multiplexer unit, for being coupled from the downlink radio-frequency signal of multiple different systems base station, filtering and shunt being carried out to the downlink radio-frequency signal of coupling, simultaneously for receiving the upstream radio-frequency signal of multiple different systems, filtering and He Lu being carried out to the upstream radio-frequency signal of multiple different systems;

Descending combiner unit, for carrying out conjunction road to multichannel downlink radio-frequency signal;

Up branching unit, for carrying out shunt to up multiple-frequency signal, and suppresses the mutual interference signal of each standard;

Near-end light unit, for completing the conversion of downlink radio-frequency signal to descending photosignal, uplink optical signal is to the conversion of upstream radio-frequency signal;

Descending optical branching unit, for being divided into multiple-channel output by light signal.

Preferably, described multifrequency near-end unit comprises further:

Modulator-demod, for providing the radio channel of remote monitoring for described multifrequency near-end unit;

Monitoring unit, for controlling the work of described multifrequency near-end unit, provides various alarm detection, local monitor and remote monitoring function simultaneously;

Power subsystem, for providing power supply for equipment, when exchanging power failure, provides alarm signal to described monitoring unit.

Preferably, described multifrequency far-end capping unit comprises:

Far-end light unit, completes the conversion of downlink optical signal to downlink radio-frequency signal, and monitor message to the conversion of uplink optical signal, and is modulated on light signal by upstream radio-frequency signal, and by Optical Fiber Transmission, the interconnection realizing far and near terminal monitor message is exchanged visits;

The descending branching unit of multifrequency far-end capping unit: shunt is carried out to descending multiple-frequency signal and exports;

The up branching unit of multifrequency far-end capping unit: conjunction road is carried out to up multiple-frequency signal and exports;

Monitoring unit: the work controlling whole multifrequency far-end capping unit, provides the function such as various alarm detection, local monitor, remote monitoring simultaneously;

The power amplification integrated unit of multifrequency LNA, it comprises LNA unit and power amplifier unit, LNA unit is for amplifying the upward signal of reception, there is low noise factor and port Impedance, LNA is built-in with numerical-control attenuator simultaneously, can regulate complete machine gain, power amplifier unit is responsible for power signal being amplified to setting;

Multiplexer unit, carries out filtering and shunt to upward signal, carries out filtering close road to downstream signal.

Preferably, the optical fiber of Same Wavelength is adopted to transmit up-downgoing light signal in described many net fusion Fiber Access Systems.

Preferably, described smooth TU Trunk Unit comprises:

From light unit, complete the conversion of radiofrequency signal-light signal, light signal-radiofrequency signal; And monitor message be modulated on light signal, by Optical Fiber Transmission, the interconnection realizing far and near terminal monitor message is exchanged visits;

Key light unit, completes the conversion of radiofrequency signal-light signal, light signal-radiofrequency signal; And monitor message be modulated on light signal, by Optical Fiber Transmission, the interconnection realizing far and near terminal monitor message is exchanged visits; Optical branching unit, is divided into multiple-channel output by light signal.

Preferably, described multifrequency far-end capping unit extends to 128.

Preferably, described near-end light unit is sent by single optical fiber interface downlink optical signal, is received by multiple optical fiber interface uplink optical signal, and Qie Duimei road light signal carries out separate detection.

As can be seen from the above technical solutions, the embodiment of the present invention has the following advantages:

(1) by a set of Fiber Access System, signal transmission is carried out to the mobile communications network of different systems, reduce network topology and device density and complexity, make extension of network easier;

(2) 1 the maximum easily extensible to 128 of multifrequency near-end unit multifrequency far-end capping units, improve systematic function greatly;

(3) fibre system adopts the optical fiber of same optical wavelength to transmit light signal, can reduce the cost of optical module, thus effectively reduction system realizes cost, and system is more easily safeguarded;

(4) the near-end light unit light signal load mode that adopts 18 to receive, and every road light signal separate detection, auto-compensation link load, utilizes radio frequency to close the mode on road, reduces optical path loss, effectively improve transmission range.

Accompanying drawing explanation

Fig. 1 is the multiple networks fusion Fiber Access System structural representation of the embodiment of the present invention one;

Fig. 2 is each modular structure schematic diagram of multiple networks fusion Fiber Access System of the embodiment of the present invention one;

Fig. 3 is the network topology structure schematic diagram of the multiple networks fusion Fiber Access System of the embodiment of the present invention two;

Fig. 4 is the structural representation of the multiple networks fusion Fiber Access System of the embodiment of the present invention three;

Fig. 5 is each modular structure schematic diagram of the multiple networks fusion Fiber Access System of the embodiment of the present invention three;

Fig. 6 is the network topology structure schematic diagram of the multiple networks fusion Fiber Access System of the embodiment of the present invention four.

Embodiment

For enabling above-mentioned purpose of the present invention, feature and advantage clearly, below in conjunction with the drawings and specific embodiments, the present invention is further detailed explanation.

With reference to figure 1, be depicted as the multiple networks fusion Fiber Access System structural representation of the embodiment of the present invention one, multiple networks fusion Fiber Access System is used for merging the mobile communications network of multiple types, CMDA can be comprised, DCS, the 2G of the standards such as WCDMA and 3G network, the network formats that can provide according to operator in specific implementation is disposed, thus the communication connection realized between base station and terminal, comprising a multifrequency near-end unit 10 and a multifrequency far-end capping unit 20, multifrequency near-end unit 10 is for being coupled from the downlink radio-frequency signal of base station, multifrequency far-end capping unit 20 is supplied to provide radio frequency signal to terminal by optical fiber after converting downlink optical signal to, and receive the uplink optical signal that multifrequency far-end capping unit 20 passed over by optical fiber, base station is sent to communicate, multifrequency far-end capping unit 20 converts downlink radio-frequency signal to for the downlink optical signal provided by multifrequency near-end unit 10, for terminal provides radio frequency signal, and receive the upstream radio-frequency signal of self terminal, be supplied to multifrequency near-end unit by optical fiber after converting described upstream radio-frequency signal to uplink optical signal.

Further, the concrete module diagram of multifrequency near-end unit 10 and multifrequency far-end capping unit 20 is see Fig. 2, and multifrequency near-end unit 10 comprises:

Multiplexer unit 101, for being coupled from the downlink radio-frequency signal of multiple different systems base station, filtering and shunt are carried out to the downlink radio-frequency signal of coupling, form multichannel downlink radio-frequency signal, simultaneously for receiving the upstream radio-frequency signal of multiple different systems, filtering and He Lu are carried out to the upstream radio-frequency signal of multiple different systems, form a road coupling upstream radio-frequency signal, the performance of multiplexer unit, the noise factor of direct influential system, spurious emissions, wherein noise factor refers to that tested repeater is within the scope of working band, the ratio of input signal-to-noise ratio and output signal-to-noise ratio during normal work, spurious emissions refer to removing working carrier frequency and with normal modulation associated side beyond frequency on transmitting.Because in system, multiplexer unit 101 is placed on the position of the first order, the size of multiplexer Insertion Loss directly has influence on the noise factor of whole system, the Insertion Loss of the multiplexer unit 101 that native system adopts is less than 1dB, effectively ensure that the noise factor of whole system; Between each frequency range of multiplexer unit 101 adopted in system Out-of-band rejection is greater than 90dB, isolation is greater than 85dB, the band stray that system produces can be suppressed by multiplexer unit, and the high-isolation of multiplexer unit ensures that the descending output factors in repeater does not disturb uplink input end to cause signal to noise ratio reduce and cause systematic function to decline.

Descending combiner unit 102, only adopt single near-end light unit 104 from reducing costs upper consideration near-end unit, the multichannel downstream signal exported from multiplexer unit 101 enters descending combiner unit 102 pairs of multichannel downlink radio-frequency signals to carry out conjunction road and then enters near-end light unit 104 input port;

Up branching unit 103, for carrying out shunt to up multiple-frequency signal, and the mutual signal of each standard is suppressed, such as CDMA, DCS, WCDMA multisystem repeater, on uplink, CDMA is up, DCS is up for up branching unit 103 pairs, provide the suppression being greater than 50dB between up three frequency ranges of WCDMA, ensures that entering LNA power amplifier unit is single frequency band signal;

Near-end light unit 104, for completing the conversion of downlink radio-frequency signal to downlink optical signal, uplink optical signal is to the conversion of upstream radio-frequency signal; Descending optical branching unit 105, light signal is received in order to allow every great distance end unit, light signal is divided into multiple-channel output, and ensure that light unit in every great distance end unit can sensed light signal separately, system of being convenient to realizes the automatic adjustment of System Link Gain by the detection of light signal strength.

Power and the monitoring of signal to realize carrying out equipment to multifrequency near-end unit 10, multifrequency near-end unit 10 comprises further: power subsystem 106, for providing power supply for equipment, exchange have a power failure time, provide alarm signal to described monitoring unit; Monitoring unit 107, for controlling the work of described multifrequency near-end unit, provides various alarm detection, local monitor and remote monitoring function simultaneously; Modem unit 108, for providing the radio channel of remote monitoring for described multifrequency near-end unit.

Multifrequency near-end unit 10 and multifrequency far-end capping unit 20 is adopted directly to carry out the mode expanded, a maximum easily extensible of multifrequency near-end unit 10 8 multifrequency far-end capping units, its network topology structure figure as shown in Figure 3, the noise of the fusion of net more than this kind Fiber Access System is analyzed, to illustrate that system can ensure the normal work of system under this kind of networking mode below.

In systems in which, simultaneously some device works in all systems, as light unit (comprising near-end light unit and far-end light unit) and multiplexer unit, non-linear due to device, is certain to produce some nonlinearity products, and as shown in table 1 is intermodulation frequency result of calculation between system, calculated by intermodulation frequency between different mobile communication system, can find out produce between different system 2 rank, 3 rank intermodulation, more high-order can corresponding reduction, does not consider here.

Because power output is less, do not consider the intermodulation of the passive devices such as multiplexer unit, mainly consider the third order intermodulation of light unit, third order intermodulation refers to when two signals are in a linear system, the first-harmonic of the second harmonic of a signal and another signal is made to produce beat (mixing) parasitic signal produced afterwards because non-linear factor exists, and the noise of light unit and intermodulation performance can interact, all affect larger on complete machine index.

2 rank produced between mutual according to each system uplink signal of upper table, 3 rank intermodulation all can not be dropped in upstream band; According to reality test, up smooth unit is when input, output are-10dBm, and IMD3 >-60dBc, can meet the intermodulation requirement of up-45dBc after suitably distributing complete machine gain power.

According to table 1,2 rank produced between downstream signal, 3 rank intermodulation are likely dropped in working band, mainly appear at the second order inter-modulation produced between CDMA-DCS up-link and can drop in CDMA downlink working frequency range.According to light unit testing result, in double-tone input, when every carrier wave input, output 0dBm, third order intermodulation is 55dBc; Second order inter-modulation is 40dBc; According to descending gain, power designs, every system is-11dBm to the input signal strength of light unit, so the third order intermodulation of the actual generation of light unit is probably-68dBc, second order inter-modulation-51dBc, intermodulation index request can be met, therefore intermodulation between these three standard systems need not be considered in design, TD time division duplex just will consider the interference between system, may produce interference to electronic switch.

Between table 1 system, intermodulation frequency calculates

Make an uproar analysis in the end:

Direct end uplink gain 33dB multiplexer unit Insertion Loss 1dB, LNA power amplifier unit gain 40dB, noise factor 0.8dB, up combiner unit Insertion Loss 2dB, light cellular system gain 0dB, noise 37dB, up branching unit Insertion Loss 2dB.

During by n noise network cascade, total noise factor can represent by following relation:

$F=F_1+\frac{F_2-1}{G_1}+\frac{F_2-1}{G_1\·G_2}+...\frac{F_n-1}{G_1\·G_2...G_{n-1}}$

Noise estimation when can draw system cascade is as follows

Noise factor during 1 near-end unit+1 far-end capping unit:

$\mathrm{NF}=10\lg ({10}^{0.1}+\frac{{10}^{0.08}-1}{{10}^{-0.1}}+\frac{{10}^{0.2}-1}{{10}^{-0.1+4}}+\frac{{10}^{3.7}-1}{{10}^{-0.1+4+(-0.2)}}+\frac{{10}^{0.2}-1}{{10}^{-0.1+4+(-0.2)+0}}+\frac{{10}^{0.1}-1}{{10}^{-0.1+4+(-0.2)+0+(-0.2)}})=3.99$

Make an uproar at the bottom of repeater to receiver as-174dBm/Hz+53dB/200KHz-43dB (path loss)+33dB (gain)+3.99 (noise factor)=-127.01dBm

1 near-end unit+8 far-end capping units: be equivalent to uply increase 9dB when being input to noise ratio 1 remote termination of far-end capping unit, total noise factor is about 12.99dB.

In order to improve multifrequency near-end unit to the extended capability of multifrequency far-end capping unit, when setting up multiple networks fusion Fiber Access System, the light signal of multi-frequency optical TU Trunk Unit to multifrequency near-end unit, multifrequency far-end capping unit can be adopted to carry out relaying amplification, improve the driving force of nearly far-end capping unit.

The many nets be made up of multifrequency near-end unit, multi-frequency optical TU Trunk Unit and multifrequency far-end capping unit merge its structural representation of Fiber Access System as shown in Figure 4, as shown in Figure 5, multi-frequency optical TU Trunk Unit comprises light unit, power subsystem, monitoring unit and the row light converting interface of totally 16 mouthfuls to concrete module diagram; Wherein light unit is made up of two parts, and adopting from light unit 301 and key light unit 302, two light unit of being connected with multifrequency far-end capping unit 30 of being connected with near-end unit independently controls, be radio signal transmission between light unit.Be integrated with 8 road light detector tubes from light unit inside 302,8 road light signal inputs can be allowed simultaneously; The effect of light converting interface is connected for light unit tail optical fiber provides with optoelectronic integration joint tail optical fiber.Cabinet panel there are 8 optical fiber, power supply integration interface, 8 multifrequency far-end capping units can be connect simultaneously.Therefore many nets of this kind of multi-frequency optical TU Trunk Unit composition are adopted to merge arbitrary multifrequency far-end capping unit within the most easily extensible to 128 of 1 multifrequency near-end unit of Fiber Access Systems.

Be illustrated in figure 61 multifrequency near-end unit expands 128 multifrequency far-end capping units network configuration topological diagram by 1 multi-frequency optical TU Trunk Unit, the noise of the fusion of net more than this kind Fiber Access System is analyzed, to illustrate that system can ensure the normal work of system under this kind of networking mode below.

System noise is analyzed as follows:

Noise factor during 1 near-end unit+1 relaying light unit+1 far-end capping unit:

$\mathrm{NF}=10\lg ({10}^{0.1}+\frac{{10}^{0.08}-1}{{10}^{-0.1}}+\frac{{10}^{0.2}-1}{{10}^{-0.1+4}}+\frac{{10}^{3.7}-1}{{10}^{-0.1+4+(-0.2)}}+\frac{{10}^{3.7}-1}{{10}^{-0.1+4+(-0.2)}}+\frac{{10}^{0.2}-1}{{10}^{-0.1+4+4(-0.2)+0}}+\frac{{10}^{0.1}-1}{{10}^{-0.1+4+(-0.2)+0+(-0.2)}})=5.45$

1 near-end unit+1 relaying light unit+8 far-end capping units: be equivalent to uply increase 9dB when being input to noise ratio 1 near-end unit+1 far-end capping unit of far-end capping unit, total noise factor is about 14.45dB.

1 near-end unit+16 relaying light unit+128 far-end capping units: be equivalent to uply increase 12dB when being input to noise ratio 1 near-end unit+1 relaying light unit+8 far-end capping units of far-end capping unit, total noise factor is 26.45dB.

Make an uproar at the bottom of receiver: P _bts-noise=10log (KTB)+NF _btsfor base station input noise level (dB); Work as NF _rep=NF _bts=5dB

P _Bts-noise＝-174dBm/Hz+53dB/200K+5dB＝-116dBm

Get receiver sensitivity :-102dBm

In 1 near-end unit+8 light TU Trunk Units+64 far-end capping unit situations:

Direct end uplink output noise level:

P _rep-noise=10log (KTB)+NF _rep+ G _rep(dB value)

The noise level P that direct end uplink exports _rep-noiseafter up path loss, be sent to base station, inject the noise of repeater at base station receiver input, the noise level being incorporated into base station is

P _rep-inj＝P _rep-noise-Ld(dB)＝10log(KTB)+NF _rep+G _rep-Ld(dB)

P _rep-inj=-174dBm+53dB+14.45dB+33dB (gain)-43dB (path loss)=-116.5dBm

Due to the introducing of repeater noise, will be the repeater noise sum of base station noise and introducing in total input noise of base station input, be shown below:

P _{Bts-noise-Total}＝P _Bts-noise+P _rep-inj

P in formula _bts-noise=10log (KTB)+NF _btsfor base station input noise level (dB);

From above formula, the introducing of repeater, will the noise level of base station receiver input be increased, this noise incremental quantity dB value be expressed as:

$\mathrm{\Δ}{\mathrm{NF}}_{\mathrm{Bts}-\mathrm{rise}}=10\log \left[\frac{P_{\mathrm{Bts}-\mathrm{noise}}+P_{\mathrm{rep}-\mathrm{inj}}}{P_{\mathrm{Bts}-\mathrm{noise}}}\right]\left(\mathrm{dB}\right)$

$=10\log =\log \left[\frac{{10}^{\frac{P_{\mathrm{Bts}-\mathrm{noise}\left(\mathrm{dB}\right)}}{10}}+{10}^{\frac{P_{\mathrm{rep}-\mathrm{inj}\left(\mathrm{dB}\right)}}{10}}}{{10}^{\frac{P_{\mathrm{Bts}-\mathrm{noise}\left(\mathrm{dB}\right)}}{10}}}\right]$

By P _bts-noiseand P _rep-injsubstitute into above formula, then at the noise incremental quantity that base station input is introduced by repeater be:

N _rise＝(NF _rep-NF _Bts)+(G _rep-Ld)＝(14.45-5)+(33-43)＝-0.55(dB)

$\mathrm{\Δ}{\mathrm{NF}}_{\mathrm{Bts}-\mathrm{rise}}=10\log [1+{10}^{\frac{{\mathrm{NF}}_{\mathrm{rep}}-{\mathrm{NF}}_{\mathrm{Bts}}+G_{\mathrm{rep}}-\mathrm{Ld}}{10}}]\left(\mathrm{dB}\right)=10\log [1+{10}^{\frac{N_{\mathrm{rise}}}{10}}]\left(\mathrm{dB}\right)=2.74\mathrm{dB}$

With make an uproar at the bottom of receiver superpose after for P _{bts-noise-Total}=-113.25dBm, under certain error rate, signal to noise ratio requires as 14dB; So sensitivity is

-113.25+14＝-99.25dBm

Covering edge mobile phone received field strength is-85dBm, and repeater up-downgoing gain is 33dBm, and descending power is 27dBm, DCS mobile phone maximum transmission power 30dBm, base station transmitting power 43dBm.

Be 30+ (-85-43)=-98dBm at cell-edge position mobile phone to the peak signal of base station, meet call requirement.

In 1 near-end unit+16 light TU Trunk Units+128 far-end capping unit situations:

Repeater bottom noise is :-174dBm+53dB-43dB (path loss)+27dB (gain)+26.45 (noise factor)=-104.5dBm

N _rise＝(NF _rep-NF _Bts)+(G _rep-Ld)＝(26.45-5)+(33-43)＝11.45(dB)

$\mathrm{\Δ}{\mathrm{NF}}_{\mathrm{Bts}-\mathrm{rise}}=10\log [1+{10}^{\frac{{\mathrm{NF}}_{\mathrm{rep}}-{\mathrm{NF}}_{\mathrm{Bts}}+G_{\mathrm{rep}}-\mathrm{Ld}}{10}}]\left(\mathrm{dB}\right)$

$=10\log [1+{10}^{\frac{N_{\mathrm{rise}}}{10}}]\left(\mathrm{dB}\right)=14.5\mathrm{dB}$

With make an uproar at the bottom of receiver superpose after for-101.5dBm, under certain error rate, signal to noise ratio requires as 14dB, so sensitivity is

-109.2+14＝-95.2dBm

Larger to base station acuity worsens, cell-edge call requirement is not met yet, in order to reduce the impact on base station, and when more remote termination, overall noise coefficient is definite value substantially, can not raise because of repeater gain reduction, repeater up-downgoing gain can be reduced to improve the end and make an uproar, improve base station sensitivity.

If within requiring acuity worsens 3dB, then require that repeater bottom noise is the same with base station bottom noise, repeater bottom noise :-110.2dBm during maximum gain, make an uproar at the bottom of receiver-116dBm, so all remote termination up-downgoing gain reduction 6dB can meet the demands, now repeater also has the power output of 21dBm, still can ensuring coverage.

Net fusion Fiber Access System to one provided by the present invention to be above described in detail more, for one of ordinary skill in the art, according to the thought of the embodiment of the present invention, all will change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention.

Claims (5)

1. more than one kind, net merges Fiber Access System, it is characterized in that, for merging the mobile communications network of multiple types, realize the communication connection between base station and terminal, comprise one or more multifrequency far-end capping unit of a multifrequency near-end unit and expansion, and one or more multi-frequency optical TU Trunk Unit;

Described multifrequency near-end unit is for being coupled from the downlink radio-frequency signal of base station, described multifrequency far-end capping unit is supplied to provide radio frequency signal to terminal by optical fiber after converting downlink optical signal to, and receive the uplink optical signal that far end device passed over by optical fiber, send to described base station to communicate;

Described multifrequency far-end capping unit is used for converting the downlink optical signal that described multifrequency near-end unit provides to downlink radio-frequency signal, for terminal provides wireless communication signals, and receive the upstream radio-frequency signal of self terminal, be supplied to described multifrequency near-end unit by optical fiber after converting described upstream radio-frequency signal to uplink optical signal;

Described multi-frequency optical TU Trunk Unit is used for being arranged between described multifrequency near-end unit and described multifrequency far-end capping unit, makes a multifrequency near-end unit easily extensible more multifrequency far-end capping unit;

Described multifrequency near-end unit comprises:

Multiplexer unit, for being coupled from the downlink radio-frequency signal of multiple different systems base station, filtering and shunt being carried out to the downlink radio-frequency signal of coupling, simultaneously for receiving the upstream radio-frequency signal of multiple different systems, filtering and He Lu being carried out to the upstream radio-frequency signal of multiple different systems;

Descending combiner unit, for carrying out conjunction road to multichannel downlink radio-frequency signal;

Up branching unit, for carrying out shunt to up multiple-frequency signal, and suppresses the mutual interference signal of each standard;

Near-end light unit, for completing the conversion of downlink radio-frequency signal to descending photosignal, uplink optical signal is to the conversion of upstream radio-frequency signal;

Descending optical branching unit, for being divided into multiple-channel output by light signal;

Described near-end light unit is sent by single optical fiber interface downlink optical signal, is received by multiple optical fiber interface uplink optical signal, and Qie Duimei road light signal carries out separate detection;

Described multifrequency far-end capping unit comprises:

Far-end light unit, completes the conversion of downlink optical signal to downlink radio-frequency signal, and monitor message to the conversion of uplink optical signal, and is modulated on light signal by upstream radio-frequency signal, and by Optical Fiber Transmission, the interconnection realizing far and near terminal monitor message is exchanged visits;

The descending branching unit of multifrequency far-end capping unit: shunt is carried out to descending multiple-frequency signal and exports;

The up combiner unit of multifrequency far-end capping unit: conjunction road is carried out to up multiple-frequency signal and exports;

Monitoring unit: the work controlling whole multifrequency far-end capping unit, provides various alarm detection, local monitor, remote monitoring simultaneously;

The power amplification integrated unit of multifrequency LNA, it comprises LNA unit and power amplifier unit, LNA unit is for amplifying the upward signal of reception, there is low noise factor and port Impedance, LNA unit is built-in with numerical-control attenuator simultaneously, can regulate complete machine gain, power amplifier unit is responsible for power signal being amplified to setting;

Multiplexer unit, carries out filtering and shunt to upward signal, carries out filtering close road to downstream signal.

2. many nets according to claim 1 merge Fiber Access System, and it is characterized in that, described multifrequency near-end unit comprises further:

Modulator-demod, for providing the radio channel of remote monitoring for described multifrequency near-end unit;

Monitoring unit, for controlling the work of described multifrequency near-end unit, provides various alarm detection, local monitor and remote monitoring function simultaneously;

Power subsystem, for providing power supply for equipment, when exchanging power failure, provides alarm signal to described monitoring unit.

3. according to claim 1 how net merges Fiber Access System, it is characterized in that: adopt the optical fiber of Same Wavelength to transmit up-downgoing light signal in described many net fusion Fiber Access Systems.

4. many nets according to claim 1 merge Fiber Access System, and it is characterized in that, described multi-frequency optical TU Trunk Unit comprises:

From light unit, complete the conversion of radiofrequency signal-light signal, light signal-radiofrequency signal; And monitor message be modulated on light signal, by Optical Fiber Transmission, the interconnection realizing far and near terminal monitor message is exchanged visits;

Key light unit, completes the conversion of radiofrequency signal-light signal, light signal-radiofrequency signal; And monitor message be modulated on light signal, by Optical Fiber Transmission, the interconnection realizing far and near terminal monitor message is exchanged visits; Optical branching unit, is divided into multiple-channel output by light signal.

5. the many nets according to any one of Claims 1-4 merge Fiber Access System, it is characterized in that: described multifrequency far-end capping unit extends to 128.