CN102263595A - Multi-network fiber access system - Google Patents

Abstract

The embodiment of the invention provides a multi-network fiber access system which has higher multi-frequency far-end coverage unit expansion capability, is provided with wider network coverage, and has higher coverage signals. The multi-network fiber access system comprises a multi-frequency near-end unit and a multi-frequency far-end coverage unit, wherein the multi-frequency near-end unit is used for coupling downlink radio-frequency signals sent from a base station, converting the downlink radio-frequency signals into downlink optical signals and then supplying the downlink optical signals to the multi-frequency far-end coverage unit through a fiber so as to supply wireless radio-frequency signals to the terminal, and also receiving uplink optical signals sent by a far-end device through a fiber and transmitting the uplink optical signals to the base station for communication; and the multi-frequency far-end coverage unit is used for converting the downlink radio-frequency signals supplied by the multi-frequency near-end unit into downlink optical signals and supplying wireless communication signals to the terminal, and also receiving uplink radio-frequency signals sent from the terminal, converting the uplink radio-frequency signals into uplink optical signals and then supplying the uplink optical signals to the multi-frequency near-end unit through a fiber.

Description

Many nets merge Fiber Access System

Technical field

The present invention relates to wireless communication field, relate in particular 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 standard, 3G network need the indoor and outdoor network coverage simultaneously.

Traditional mobile communication indoor distribution system generally adopts coaxial cable system to carry out networking, but increase along with 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 bigger, cause that networking influence is wide, great in constructing amount, the construction period is long, the website operability of meeting an urgent need is slightly poor; Construction easily causes some destruction to building, for example metope perforation, the interior cabling of cable smallpox etc., and exposing cable needs the suit pvc pipe, can allow fitting-up be partially damaged, and makes administrative office, owner to this strong reaction, and acceptance is relatively poor; The whole system complex structure, take up room, install, the dismounting difficulty, maintenance workload is big; Contradiction is more outstanding in shared by multiple systems design, networking and when safeguarding.

At above situation, with respect to traditional coaxial cable connecting system, introduce Fiber Access System, Fiber Access System have the life-span long, reliability is high, the advantage of strong interference immunity, optical transmission has very strong extended capability, and realizes the fusion of a plurality of standards easily.

Can accomplish to expand 16 multifrequency far-end capping units on 1 multifrequency near-end of existing fiber connecting system Element Theory, but actual open with maintenance process in telephone traffic can occur and concentrate on a certain sector, cause traffic congestion and upstream noise problem rambunctious easily, introduced the noise of LNA and optical device, directly have influence on the receiving sensitivity of base station, reduce the coverage of base station, therefore only can expand 4 multifrequency far-end capping units in actual use, the expansion number again increase can to cause the up end to be made an uproar excessive, serious interference is caused in the base station; Secondly, the legacy equipment optical signal transmission mostly adopts 1310nm and 1550nm multiplexing transmission, and device cost is higher, the multiplexing transmission data stability is low; The light unit of fibre system mostly adopts 1 to receive 1 mode in the past once more, and the extended distal end machine can only adopt the light branch, close the mode on road, and the big and every road gain loss of loss of signal is not easy to automatic adjusting.

Summary of the invention

The embodiment of the invention provides a kind of many nets to merge Fiber Access System, is used to realize a kind of bigger multifrequency far-end capping unit extended capability that has, and the network coverage is wider, covers the stronger many network integrations fibre system of signal.

The embodiment of the invention provides a kind of many nets to merge Fiber Access System, be used for the mobile communications network of multiple standard is merged, realize that the base station is connected with communication between terminals, comprise one or more multifrequency far-end capping unit at least of a multifrequency near-end unit and expansion

Described multifrequency near-end unit the downlink radio-frequency signal that is used to be coupled from the base station, offer described multifrequency far-end capping unit to provide radio frequency signal by optical fiber after converting downlink optical signal to terminal, and receive described far end device by the uplink optical signal that optical fiber passes over, send to described base station and 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 the up radiofrequency signal of receive self terminal, offer described multifrequency near-end unit by optical fiber after converting described up radiofrequency signal to uplink optical signal.

Preferably, further comprise one or more multifrequency optical relay unit,

Described multifrequency optical relay unit is used to be arranged between described multifrequency near-end unit and the described multifrequency far-end capping unit, makes a multifrequency near-end unit can expand more multifrequency far-end capping unit.

Preferably, described multifrequency near-end unit comprises:

The multiplexer unit, downlink radio-frequency signal from a plurality of different systems base station is used to be coupled, downlink radio-frequency signal to coupling carries out filtering and shunt, is used to receive the up radiofrequency signal of a plurality of different systems simultaneously, and the up radiofrequency signal of a plurality of different systems is carried out filtering and He Lu;

Descending combiner unit is used for the multichannel downlink radio-frequency signal is closed the road;

Up branching unit is used for up multiple-frequency signal is carried out shunt, and the mutual interference signal of each standard is suppressed;

Near-end light unit is used to finish the conversion of downlink radio-frequency signal to descending photosignal, and uplink optical signal is to the conversion of up radiofrequency signal;

Descending optical branching unit is used for the light signal demultiplexing is exported.

Preferably, described multifrequency near-end unit further comprises:

Modulator-demod is used to described multifrequency near-end unit that the radio channel of remote monitoring is provided;

Monitoring unit is used to control the work of described multifrequency near-end unit, and various alarm detection, local monitor and remote monitoring function are provided simultaneously;

Power subsystem is used to equipment that power supply is provided, and when exchanging power failure, provides alarm signal to described monitoring unit.

Preferably, described multifrequency far-end capping unit comprises:

The conversion of downlink optical signal to downlink radio-frequency signal finished in far-end light unit, and up radiofrequency signal arrives the conversion of uplink optical signal, and monitor message is modulated on the light signal, by Optical Fiber Transmission, realizes that the interconnection of far and near terminal monitor message is exchanged visits;

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

The up branching unit of multifrequency far-end capping unit: up multiple-frequency signal is closed road output;

Monitoring unit: control the work of whole multifrequency far-end capping unit, functions such as various alarm detection, local monitor, remote monitoring are provided simultaneously;

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

The multiplexer unit carries out filtering and shunt to upward signal, downstream signal is carried out filtering close the road.

Preferably, adopt the optical fiber of same wavelength that the up-downgoing light signal is transmitted in described many net fusion Fiber Access Systems.

Preferably, described optical relay unit comprises:

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

The conversion of radiofrequency signal-light signal, light signal-radiofrequency signal is finished in the key light unit; And monitor message is modulated on the light signal,, realizes that the interconnection of far and near terminal monitor message is exchanged visits by Optical Fiber Transmission; Optical branching unit is exported the light signal demultiplexing.

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

Preferably, described near-end light unit sends by the single optical fiber interface downlink optical signal, uplink optical signal is received by a plurality of optical fiber interfaces, and every road light signal is carried out separate detection.

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

(1) by a unjacketed optical fiber connecting system mobile communications network of different systems is carried out the signal transmission, reduce network topology and device density and complexity, make extension of network easier;

(2) 1 multifrequency near-end unit maximums can extend to 128 multifrequency far-end capping units, have promoted systematic function greatly;

(3) fibre system adopts the optical fiber of same optical wavelength that light signal is transmitted, and can reduce the cost of optical module, thereby effectively reduction system realizes cost, and makes the easier maintenance of system;

(4) near-end light unit adopts 1 the 8 light signal load mode of receiving, and every road light signal separate detection, compensates link load automatically, utilizes radio frequency to close the mode on road, reduces optical path loss, effectively improves transmission range.

Description of drawings

Fig. 1 is many network integrations Fiber Access System structural representation of the embodiment of the invention one;

Fig. 2 is each modular structure schematic diagram of many network integrations Fiber Access System of the embodiment of the invention one;

Fig. 3 is the network topology structure schematic diagram of many network integrations Fiber Access System of the embodiment of the invention two;

Fig. 4 is the structural representation of many network integrations Fiber Access System of the embodiment of the invention three;

Fig. 5 is each modular structure schematic diagram of many network integrations Fiber Access System of the embodiment of the invention three;

Fig. 6 is the network topology structure schematic diagram of many network integrations Fiber Access System of the embodiment of the invention four.

Embodiment

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

With reference to figure 1, be depicted as many network integrations Fiber Access System structural representation of the embodiment of the invention one, many network integrations Fiber Access System is used for the mobile communications network of multiple standard is merged, can comprise CMDA, DCS, the 2G of standards such as WCDMA and 3G network, can dispose according to the network formats that the operator provides in the specific implementation, thereby realize that the base station is connected with communication between terminals, comprising a multifrequency near-end unit 10 and a multifrequency far-end capping unit 20, multifrequency near-end unit 10 the downlink radio-frequency signal that is used to be coupled from the base station, offer multifrequency far-end capping unit 20 to provide radio frequency signal by optical fiber after converting downlink optical signal to terminal, and receive multifrequency far-end capping unit 20 by the uplink optical signal that optical fiber passes over, send to the base station and communicate; Multifrequency far-end capping unit 20 is used for converting the downlink optical signal that multifrequency near-end unit 10 provides to downlink radio-frequency signal, for terminal provides radio frequency signal, and the up radiofrequency signal of receive self terminal, offer multifrequency near-end unit by optical fiber after converting described up radiofrequency signal to uplink optical signal.

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

Multiplexer unit 101, downlink radio-frequency signal from a plurality of different systems base station is used to be coupled, downlink radio-frequency signal to coupling carries out filtering and shunt, form the multichannel downlink radio-frequency signal, be used to receive the up radiofrequency signal of a plurality of different systems simultaneously, up radiofrequency signal to a plurality of different systems is carried out filtering and He Lu, form the one tunnel up radiofrequency signal that is coupled, the performance of multiplexer unit, directly influence the noise factor of system, spurious emissions, wherein noise factor is meant tested repeater in the working band scope, the ratio of input signal-to-noise ratio and output signal-to-noise ratio during operate as normal; Spurious emissions is meant the emission of removing on working carrier frequency and the frequency in addition of relevant sideband with normal modulation.Because multiplexer unit 101 is placed on the position of the first order in the system design, 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 adopted has effectively guaranteed the noise factor of whole system less than 1dB; Band between multiplexer unit 101 each frequency range that adopt in the system suppresses greater than 90dB, isolation outward greater than 85dB, outer spuious can the inhibition by the multiplexer unit of the band that system produced, the high-isolation of multiplexer unit guarantees under the repeater that line output is spuious and does not disturb up input to cause signal to noise ratio to reduce and cause systematic function to descend.

Descending combiner unit 102, consider that from reducing cost the near-end unit only adopts single near-end light unit 104, the multichannel downstream signals of 101 outputs enter 102 pairs of multichannel downlink radio-frequency signals of descending combiner unit and close the road and enter 104 input ports, near-end light unit then from the multiplexer unit;

Up branching unit 103, be used for up multiple-frequency signal is carried out shunt, and the mutual signal of each standard suppressed, for example for CDMA, a DCS, WCDMA multisystem repeater, on up link, CDMA is up, DCS is up for 103 pairs of up branching units, the inhibition greater than 50dB is provided between up three frequency ranges of WCDMA, guarantees that entering the LNA power amplifier unit is the single frequency band signal;

Near-end light unit 104 is used to finish the conversion of downlink radio-frequency signal to downlink optical signal, and uplink optical signal is to the conversion of up radiofrequency signal; Descending optical branching unit 105, in order to allow every great distance end unit receive light signal, with light signal demultiplexing output, guarantee the light unit sensed light signal separately in every great distance end unit, the detection of the system of being convenient to by light signal strength realizes the automatic adjustment that system link gains.

In order to realize that multifrequency near-end unit 10 is carried out the monitoring of power devices and signal, multifrequency near-end unit 10 further comprises: power subsystem 106, and be used to equipment that power supply is provided, when exchanging power failure, provide alarm signal to described monitoring unit; Monitoring unit 107 is used to control the work of described multifrequency near-end unit, and various alarm detection, local monitor and remote monitoring function are provided simultaneously; Modem unit 108 is used to described multifrequency near-end unit that the radio channel of remote monitoring is provided.

The mode that adopts multifrequency near-end unit 10 and multifrequency far-end capping unit 20 directly to expand, a multifrequency near-end unit 10 can be expanded 8 multifrequency far-end capping units at most, its network topology structure figure as shown in Figure 3, below the noise that merges Fiber Access System of net more than this kind analyze, can guarantee the operate as normal of system with explanation system under this kind networking mode.

In system, some device is to work in all systems simultaneously, as light unit (comprising near-end light unit and far-end light unit) and multiplexer unit, because device non-linear is certain to produce some nonlinearity products, as shown in table 1 is intermodulation frequency result of calculation between system, calculate by intermodulation frequency between the different mobile communication system, can find out 2 rank, the 3 rank intermodulation that produce between the different system, more corresponding the reducing of high-order meeting do not considered here.

Because power output is less, do not consider the intermodulation of passive devices such as multiplexer unit, it mainly is the third order intermodulation of considering the light unit, third order intermodulation is meant works as two signals in a linear system, because the non-linear factor existence makes the second harmonic of a signal and the first-harmonic of another signal produce the parasitic signal that beat (mixing) back is produced, and the noise of light unit and intermodulation performance can interact, and all influences bigger to the complete machine index.

2 rank, the 3 rank intermodulation that produce between mutually according to each system uplink signal of last table all can not drop in the upstream band; According to reality test, up smooth unit is in input, output-during 10dBm, IMD3＞-60dBc, suitably distribute the intermodulation requirement that can satisfy up-45dBc behind the complete machine gain power.

According to table 1,2 rank that produce between the downstream signal, 3 rank intermodulation might drop in the working band, mainly appear at the second order inter-modulation that produces between the CDMA-DCS up-link and can drop in the CDMA downlink working frequency range.According to light unit testing result, in the 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 to the input signal strength of light unit is-11dBm, so the third order intermodulation of the actual generation in light unit probably is-68dBc, second order inter-modulation-51dBc, can satisfy the intermodulation index request, so need not consider intermodulation between these three standard systems in the design, the TD time division duplex is just wanted the interference between taking into account system, may produce electronic switch and disturb.

Intermodulation frequency calculates between table 1 system

The end analysis of making an uproar:

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

During by n noise network cascade, total noise factor can be represented with 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 in the time of can drawing system's cascade is as follows

Noise factor during 1 near-end unit+1 far-end capping unit: $\mathrm{NF}=10\lg ({10}^{0.1}+\frac{{10}^{0.08}-1}{{10}^{-0.1}}+\frac{{10}^{0.2}-1}{{10}^{-0.1+4}}+\frac{{10}^{3.7}-1}{{10}^{-0.1+4+(-0.2)}}+\frac{{10}^{0.2}-1}{{10}^{-0.1+4+(-0.2)+0}}+\frac{{10}^{0.1}-1}{{10}^{-0.1+4+(-0.2)+0+(-0.2)}})=3.99$

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

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

In order to improve the extended capability of multifrequency near-end unit to multifrequency far-end capping unit, when setting up many network integrations Fiber Access System, can adopt multifrequency optical relay unit that the light signal of multifrequency near-end unit, multifrequency far-end capping unit is carried out the relaying amplification, improve the driving force of nearly far-end capping unit.

Many nets of being made up of multifrequency near-end unit, multifrequency optical relay unit and multifrequency far-end capping unit merge its structural representation of Fiber Access System as shown in Figure 4, concrete module diagram as shown in Figure 5, multifrequency optical relay unit comprises light unit, power subsystem, monitoring unit and a row totally 16 mouthfuls light converting interface; Wherein the light unit is made up of two parts, and adopting independently from light unit 301 and 302, two light unit, key light unit of linking to each other with multifrequency far-end capping unit 30 of linking to each other with the near-end unit controlled, be radio signal transmission between the light unit.Inner 302 integrated 8 road light detector tubes can allow the input of 8 road light signals simultaneously from the light unit; The effect of light converting interface is to be connected for light unit tail optical fiber provides with optoelectronic integration joint tail optical fiber.8 optical fiber, power supply integration interface are arranged on the cabinet panel, can connect 8 multifrequency far-end capping units simultaneously.Therefore 1 multifrequency near-end unit that the many nets that adopt this kind multifrequency optical relay unit to form merge Fiber Access System can extend to 128 with the interior far-end of multifrequency arbitrarily capping unit.

Be illustrated in figure 6 as the network configuration topological diagram of 1 multifrequency near-end unit by 128 multifrequency far-ends of 1 multifrequency optical relay unit extensions capping unit, below the noise that merges Fiber Access System of net more than this kind analyze, can guarantee the operate as normal of system with explanation system under this kind networking mode.

System noise is analyzed as follows:

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

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

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

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

Make an uproar at the bottom of the receiver: P _Bts-noise=10log (KTB)+NF _BtsBe 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

Under the far-end capping unit situation of optical relay unit+64,1 near-end unit+8:

Direct end uplink output noise level:

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

The noise level P of direct end uplink output _Rep-noiseThrough sending to the base station after the up path loss, at the noise of base station receiver input injection repeater, the noise level that is incorporated into the 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

Because 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 the formula _Bts-noise=10log (KTB)+NF _BtsBe base station input noise level (dB);

By following formula as can be known, the introducing of repeater will increase the noise level of base station receiver input, and this noise incremental quantity with the dB value representation is:

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

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

With P _Bts-noiseAnd P _Rep-injThe substitution following formula, then the noise incremental quantity of being introduced by the repeater at the base station input is:

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

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

The stack back is P with making an uproar at the bottom of the receiver _{Bts-noise-Total}=-113.25dBm, signal to noise ratio requires to be 14dB under certain error rate; So sensitivity is

-113.25+14＝-99.25dBm

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

Fringing field strong position mobile phone to the peak signal of base station be 30+ (85-43)=-98dBm, satisfy the conversation requirement.

Under the far-end capping unit situation of optical relay unit+128,1 near-end unit+16:

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 the stack back of making an uproar at the bottom of the receiver is-101.5dBm that the signal to noise ratio requirement is 14dB under certain error rate, so sensitivity is

-109.2+14＝-95.2dBm

Worsen bigger to base station sensitivity, do not satisfy the fringing field requirement of conversing by force yet, in order to reduce influence to the base station, and under the situation of more remote termination, the overall noise coefficient is definite value basically, can not reduce and not raise, can reduce the repeater up-downgoing and gain and improve the end and make an uproar, improve base station sensitivity because of repeater gain.

If require sensitivity to worsen in the 3dB, then require repeater bottom noise with make an uproar at the bottom of the base station the same, repeater bottom noise during maximum gain :-110.2dBm, make an uproar at the bottom of the receiver-116dBm, so all remote termination up-downgoing gains reduce 6dB and can meet the demands, this moment, the repeater also had the power output of 21dBm, still can guarantee to cover.

More than a kind of many nets provided by the present invention merged Fiber Access Systems be described in detail, for one of ordinary skill in the art, thought according to the embodiment of the invention, part in specific embodiments and applications all can change, in sum, this description should not be construed as limitation of the present invention.

Claims (9)

1. net merges Fiber Access System more than one kind, it is characterized in that, be used for the mobile communications network of multiple standard is merged, realize that the base station is connected with communication between terminals, one or more multifrequency far-end capping unit at least that comprises a multifrequency near-end unit and expansion

Described multifrequency near-end unit the downlink radio-frequency signal that is used to be coupled from the base station, offer described multifrequency far-end capping unit to provide radio frequency signal by optical fiber after converting downlink optical signal to terminal, and receive described far end device by the uplink optical signal that optical fiber passes over, send to described base station and 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 the up radiofrequency signal of receive self terminal, offer described multifrequency near-end unit by optical fiber after converting described up radiofrequency signal to uplink optical signal.

2. many nets according to claim 1 merge Fiber Access System, it is characterized in that, further comprise one or more multifrequency optical relay unit,

Described multifrequency optical relay unit is used to be arranged between described multifrequency near-end unit and the described multifrequency far-end capping unit, makes a multifrequency near-end unit can expand more multifrequency far-end capping unit.

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

The multiplexer unit, downlink radio-frequency signal from a plurality of different systems base station is used to be coupled, downlink radio-frequency signal to coupling carries out filtering and shunt, is used to receive the up radiofrequency signal of a plurality of different systems simultaneously, and the up radiofrequency signal of a plurality of different systems is carried out filtering and He Lu;

Descending combiner unit is used for the multichannel downlink radio-frequency signal is closed the road;

Up branching unit is used for up multiple-frequency signal is carried out shunt, and the mutual interference signal of each standard is suppressed;

Near-end light unit is used to finish the conversion of downlink radio-frequency signal to descending photosignal, and uplink optical signal is to the conversion of up radiofrequency signal;

Descending optical branching unit is used for the light signal demultiplexing is exported.

4. many nets according to claim 3 merge Fiber Access System, it is characterized in that described multifrequency near-end unit further comprises:

Modulator-demod is used to described multifrequency near-end unit that the radio channel of remote monitoring is provided;

Monitoring unit is used to control the work of described multifrequency near-end unit, and various alarm detection, local monitor and remote monitoring function are provided simultaneously;

Power subsystem is used to equipment that power supply is provided, and when exchanging power failure, provides alarm signal to described monitoring unit.

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

The conversion of downlink optical signal to downlink radio-frequency signal finished in far-end light unit, and up radiofrequency signal arrives the conversion of uplink optical signal, and monitor message is modulated on the light signal, by Optical Fiber Transmission, realizes that the interconnection of far and near terminal monitor message is exchanged visits;

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

The up branching unit of multifrequency far-end capping unit: up multiple-frequency signal is closed road output;

Monitoring unit: control the work of whole multifrequency far-end capping unit, functions such as various alarm detection, local monitor, remote monitoring are provided simultaneously;

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

The multiplexer unit carries out filtering and shunt to upward signal, downstream signal is carried out filtering close the road.

6. net according to claim 1 and 2 merged Fiber Access System more, it is characterized in that: the optical fiber that described many nets merge the same wavelength of employing in the Fiber Access System transmits the up-downgoing light signal.

7. many nets according to claim 2 merge Fiber Access System, it is characterized in that described optical relay unit comprises:

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

The conversion of radiofrequency signal-light signal, light signal-radiofrequency signal is finished in the key light unit; And monitor message is modulated on the light signal,, realizes that the interconnection of far and near terminal monitor message is exchanged visits by Optical Fiber Transmission; Optical branching unit is exported the light signal demultiplexing.

8. many nets according to claim 2 merge Fiber Access System, and it is characterized in that: described multifrequency far-end capping unit extends to 128.

9. many nets according to claim 3 merge Fiber Access System, it is characterized in that: described near-end light unit sends by the single optical fiber interface downlink optical signal, uplink optical signal is received by a plurality of optical fiber interfaces, and every road light signal is carried out separate detection.

Images