Be applicable to the digital RF far-drawing system of dual communication standard
Technical field
The present invention relates to a kind of digital RF far-drawing system, relate in particular to a kind of dual communication standard that is applicable to, i.e. the digital RF far-drawing system of GSM standard and DCS standard.
Background technology
The repeater is the important supplement equipment in the mobile system Access Network, plays the effect of extending base station range and dead zone-eliminating.A kind of as the repeater, optical fiber direct amplification stands in the network optimization and is used widely.Optical fiber repeater can be divided into analog optical fiber repeater and digital RF far-drawing system two big classes.The wherein important effect of digital RF far-drawing system play more and more in mobile communication network optimization.Compare with traditional analog optical fiber repeater, digital RF far-drawing system has that power output is bigger, noise factor is lower, transmission range is longer, not interference base station, advantage such as networking is more flexible, the overlapping area of coverage time delay of far-end can be adjusted when far-end covers.
At present, though the digital RF far-drawing system on the market is of a great variety, there is not a kind of Related product that can support a plurality of communication standards simultaneously.And, to integrated and requirement equipment cost is more and more higher, therefore be necessary to develop a kind of digital RF far-drawing system that can support GSM frequency range and DCS frequency range simultaneously on the market along with the development of mobile communication cause.
Summary of the invention
The purpose of this invention is to provide a kind of digital RF far-drawing system that is applicable to the dual communication standard, to satisfy market to integrated and requirement equipment cost.
To achieve these goals, the invention provides a kind of digital RF far-drawing system that is applicable to the dual communication standard, comprise that the digital fiber radio frequency zooms out frequency-selecting near-end machine and zooms out the digital fiber radio frequency that frequency-selecting near-end machine is connected by optical fiber and described digital fiber radio frequency and zoom out the frequency-selecting remote termination
Wherein, described digital radio frequency far-pulling frequency-selecting near-end machine comprises:
GSM near-end down link is used for the GSM downlink radio-frequency signal of base station is carried out down-conversion;
DCS near-end down link is used for the DCS downlink radio-frequency signal of base station is carried out down-conversion;
GSM near-end up link, the GSM intermediate-freuqncy signal that is used for terminal number word signal processing module transmission is nearly carried out up-conversion, and the up radiofrequency signal of the GSM after the up-conversion is sent to the base station;
DCS near-end up link, the DCS intermediate-freuqncy signal that is used for terminal number word signal processing module transmission is nearly carried out up-conversion, and the up radiofrequency signal of the DCS after the up-conversion is sent to the base station;
The near-end digital signal processing module is used for the intermediate-freuqncy signal after described GSM near-end down link or the described DCS near-end down link down-conversion is carried out intermediate-freuqncy signal-digital signal conversion, Digital Down Convert processing, digital filtering processing and framing successively; The serial data that described digital radio frequency far-pulling frequency-selecting remote termination sends is separated frame, digital filtering processing, Digital Up Convert processing, digital signal-intermediate-freuqncy signal conversion successively,
Wherein, described digital radio frequency far-pulling frequency-selecting remote termination comprises:
GSM far-end down link is used for the GSM intermediate-freuqncy signal that the remote digital signal processing module sends is carried out up-conversion, linear adjustment, amplification and filtering successively;
DCS far-end down link is used for the DCS intermediate-freuqncy signal that the remote digital signal processing module sends is carried out up-conversion, linear adjustment, amplification and filtering successively;
GSM far-end up link is used for the up radiofrequency signal of GSM of portable terminal emission is carried out filtering, amplification, down-conversion successively;
DCS far-end up link is used for the up radiofrequency signal of DCS of portable terminal emission being carried out filtering successively, amplification, down-conversion;
The remote digital signal processing module is used for the serial data that described digital radio frequency far-pulling frequency-selecting near-end machine sends is separated frame, digital filtering, Digital Up Convert processing, digital signal-intermediate-freuqncy signal conversion successively; Intermediate-freuqncy signal after described GSM far-end up link or the DCS far-end up link down-conversion is carried out intermediate-freuqncy signal-digital signal conversion, Digital Down Convert processing, digital filtering processing successively, closed road processing and framing.
As seen from the above, native system digital fiber radio frequency zooms out frequency-selecting near-end machine and digital fiber radio frequency and zooms out the frequency-selecting remote termination and support double-standard.Its near-end digital signal processing module and remote digital signal processing module can provide 24 frequency adaptive frequency-selectings in two nets, and bigger advantage is arranged in practical engineering application.Compare with DCS single system digital RF far-drawing system with 2 GSM are installed simultaneously, can reduce installing space to greatest extent, reduce equipment cost.
In addition, Digital Signal Processing and digital signal optical fiber transmission technique that near-end digital signal processing module and remote digital signal processing module have adopted can realize that the signal of the long-distance transmissions of multi-carrier mobile communication signal and big capacity, great dynamic range covers.
In one embodiment of the invention, described digital radio frequency far-pulling frequency-selecting near-end machine also comprises:
The near-end monitoring module is used to monitor described GSM near-end down link, DCS near-end down link, GSM near-end up link, DCS near-end up link and near-end digital signal processing module, and monitored results is sent to the upper strata webmaster;
Described digital radio frequency far-pulling frequency-selecting remote termination also comprises:
The remote monitoring module is used to monitor described GSM far-end down link, DCS far-end down link, GSM far-end up link, DCS proximal-distal link and remote digital signal processing module, and monitored results is sent to the upper strata webmaster.
As from the foregoing, OMC integration module program has perfect self-checking alarming function and monitoring function.
In another embodiment of the present invention, described GSM near-end down link comprises:
Low-converter is used for the GSM downlink radio-frequency signal of base station is downconverted into the GSM intermediate-freuqncy signal,
Described near-end digital signal processing module comprises:
The A/D converter is used for the GSM intermediate-freuqncy signal that described low-converter produces is converted to digital signal;
Digital signal processing unit is used for the GSM digital signal down variable frequency after the described A/D converter conversion is become baseband signal, will be packaged into serial data behind the described baseband signal digital filtering;
Optical transceiver is used for converting the serial data that described digital signal processing unit produces to light signal,
Described remote digital signal processing module comprises:
Optical transceiver is used for converting the light signal that the optical transceiver of described near-end digital signal processing module sends to serial data;
Digital signal processing unit is used for that the serial data that described optical transceiver produces is separated frame and becomes baseband signal, with up-converting to digital signal behind the described baseband signal digital filtering, described digital signal is carried out the time delay adjustment,
The D/A converter is used for the adjusted digital signal of described digital signal processing unit time delay is converted to intermediate-freuqncy signal,
Described GSM far-end down link comprises:
Upconverter is used for the intermediate-freuqncy signal that the D/A converter of described remote digital signal processing module is changed is up-converted into the GSM downlink radio-frequency signal,
GSM analog predistortion module is used for the GSM downlink radio-frequency signal that described upconverter produces is carried out linearity adjustment;
The GSM power amplifier is used to amplify the linear adjusted GSM downlink radio-frequency signal of described GSM analog predistortion module;
The GSM duplexer is used for the GSM downlink radio-frequency signal after the described GSM power amplifier amplification is carried out filtering.
Like this, the descending time delay of the GSM that the digital signal processing unit in the remote digital signal processing module provides is adjusted function, can eliminate with overlapping covered delay dispersion between the different RRH in sector and disturb.
In an embodiment more of the present invention, described GSM far-end up link comprises:
The GSM duplexer is used for the up radiofrequency signal of GSM that portable terminal sends is carried out filtering;
Low noise amplifier is used to amplify the up radiofrequency signal of the filtered GSM of described GSM duplexer;
Low-converter is used for the up radiofrequency signal of GSM after the described low noise amplifier amplification is downconverted into intermediate-freuqncy signal,
Described remote digital signal processing module comprises:
The A/D converter is used for the intermediate-freuqncy signal that the low-converter of described GSM far-end up link produces is converted to digital signal;
Digital signal processing unit, be used for the GSM digital signal down variable frequency that described A/D converter produces is become baseband signal, and the GSM baseband signal carried out digital filtering and time delay adjustment, with the adjusted GSM baseband signal of all time delays close the road, and involutory road after the GSM baseband signal pack, become the GSM serial data;
Optical transceiver is used for converting the GSM serial data that described digital signal processing unit produces to light signal,
Described near-end digital signal processing module comprises:
Optical transceiver is used for converting the light signal that the optical transceiver of described remote digital signal processing module sends to the GSM serial data;
Digital signal processing unit is used for that the GSM serial data that described optical transceiver produces is separated frame and becomes baseband signal, and the GSM baseband signal is carried out being up-converted into digital signal behind the digital filtering;
The D/A converter is used for the GSM digital signal that described digital signal processing unit produces is converted to intermediate-freuqncy signal,
Described GSM near-end up link comprises:
Upconverter is used for the GSM intermediate-freuqncy signal that the D/A converter of described near-end digital signal processing module produces is up-converted to the up radiofrequency signal of GSM.
Like this, the GSM uplink time delay that the digital signal processing unit in the remote digital signal processing module provides is adjusted function, can eliminate with overlapping covered delay dispersion between the different RRH in sector and disturb.
In another embodiment of the present invention, described DCS near-end down link comprises:
Low-converter is used for the DCS downlink radio-frequency signal of base station is downconverted into intermediate-freuqncy signal,
Described near-end digital signal processing module comprises:
The A/D converter is used for the DCS intermediate-freuqncy signal that described low-converter produces is converted to digital signal;
Digital signal processing unit is used for the DCS digital signal down variable frequency after the described A/D converter conversion is become baseband signal, will be packaged into serial data behind the DCS baseband signal digital filtering;
Optical transceiver is used for converting the DCS serial data that described digital signal processing unit produces to light signal,
Described remote digital signal processing module comprises:
Optical transceiver is used for converting the light signal that the optical transceiver of described near-end digital signal processing module sends to the DCS serial data;
Digital signal processing unit is used for that the DCS serial data that described optical transceiver produces is separated frame and becomes baseband signal, with up-converting to digital signal behind the DCS baseband signal digital filtering, the DCS digital signal is carried out the time delay adjustment,
The D/A converter is used for the adjusted DCS digital signal of described digital signal processing unit time delay is converted to intermediate-freuqncy signal,
Described DCS far-end down link comprises:
Upconverter is used for the DCS intermediate-freuqncy signal that the D/A converter of described remote digital signal processing module produces is up-converted into the DCS downlink radio-frequency signal,
DCS analog predistortion module is used for the DCS downlink radio-frequency signal that described upconverter produces is carried out linearity adjustment;
The DCS power amplifier is used to amplify the linear adjusted DCS downlink radio-frequency signal of described DCS analog predistortion module;
The DCS duplexer is used for the DCS downlink radio-frequency signal after the described DCS power amplifier amplification is carried out filtering.
Like this, the descending time delay of the DCS that the digital signal processing unit in the remote digital signal processing module provides is adjusted function, can eliminate with overlapping covered delay dispersion between the different RRH in sector and disturb.
In an embodiment more of the present invention, described GSM far-end up link comprises:
The DCS duplexer is used for the up radiofrequency signal of DCS of portable terminal emission is carried out filtering;
Low noise amplifier is used to amplify the up radiofrequency signal of the filtered DCS of described DCS duplexer;
Low-converter is used for the up radiofrequency signal of DCS after the described low noise amplifier amplification is downconverted into intermediate-freuqncy signal,
Described remote digital signal processing module comprises:
The A/D converter is used for the intermediate-freuqncy signal that the low-converter of described DCS far-end up link produces is converted to digital signal;
Digital signal processing unit, be used for the DCS digital signal down variable frequency that described A/D converter produces is become baseband signal, and the DCS baseband signal carried out digital filtering and time delay adjustment, with the adjusted DCS baseband signal of all time delays close the road, and involutory road after the DCS baseband signal pack, become the DCS serial data;
Optical transceiver is used for converting the DCS serial data that described digital signal processing unit produces to light signal,
Described near-end digital signal processing module comprises:
Optical transceiver is used for converting the DCS light signal that the optical transceiver of described remote digital signal processing module sends to serial data;
Digital signal processing unit is used for that the DCS serial data that described optical transceiver produces is separated frame and becomes baseband signal, to being up-converted into digital signal behind the DCS baseband signal digital filtering;
The D/A converter is used for the DCS digital signal that described digital signal processing unit produces is converted to intermediate-freuqncy signal,
Described DCS near-end up link comprises:
Upconverter is used for the DCS intermediate-freuqncy signal that the D/A converter of described near-end digital signal processing module produces is up-converted to the up radiofrequency signal of DCS.
Like this, the DCS uplink time delay that the digital signal processing unit in the remote digital signal processing module provides is adjusted function, can eliminate with overlapping covered delay dispersion between the different RRH in sector and disturb.
In another embodiment of the present invention, the operating power of described GSM analog predistortion module is 1W, and the peak power output of GSM power amplifier is 25W.In an embodiment more of the present invention, the operating power of described DCS analog predistortion module is 1W, and the peak power output of DCS power amplifier is 25W.Like this, the output of system descending direction is pushed into GSM 60W and DCS 60W, when high power work is under GSM and two kinds of communication standards of DCS, improved the in-band intermodulation and neighboring trace rejection ratio (ACPR) index of system, satisfied the requirement of market and low equipment cost integrated digital RF far-drawing system.
In another embodiment of the present invention, the digital signal processing unit of described remote digital signal processing module also carried out noise suppressed before the GSM baseband signal behind the involutory road is packed.In an embodiment more of the present invention, the digital signal processing unit of described remote digital signal processing module also carried out noise suppressed before the DCS baseband signal behind the involutory road is packed.Like this, the upstream noise of each remote terminal is controlled, greatly reduced upstream noise phase mutual interference between each remote terminal, eliminate the influence of uplink interference the base station.
By following description also in conjunction with the accompanying drawings, it is more clear that the present invention will become, and these accompanying drawings are used to explain embodiments of the invention.
Description of drawings
Fig. 1 is the theory diagram that the present invention is applicable to the digital RF far-drawing system of dual communication standard.
Fig. 2 is that the digital fiber radio frequency of the digital RF far-drawing system of dual communication standard that is applicable to shown in Figure 1 zooms out the structured flowchart of frequency-selecting near-end machine.
Fig. 3 is that the digital fiber radio frequency of the digital RF far-drawing system of dual communication standard that is applicable to shown in Figure 1 zooms out the structured flowchart of frequency-selecting remote termination.
Fig. 4 zooms out the detailed combination block diagram that frequency-selecting near-end machine and digital fiber radio frequency shown in Figure 3 zoom out the frequency-selecting remote termination for digital fiber radio frequency shown in Figure 2.
Fig. 5 is the schematic diagram that the present invention is applicable to the star-like networking mode of digital RF far-drawing system of dual communication standard.
Fig. 6 is the schematic diagram that the present invention is applicable to the digital RF far-drawing system daisy chain type networking mode of dual communication standard.
Fig. 7 is the schematic diagram that the present invention is applicable to the digital RF far-drawing system hybridized group net mode of dual communication standard.
Embodiment
With reference now to accompanying drawing, describe embodiments of the invention, the similar elements label is represented similar elements in the accompanying drawing.
Fig. 1 is the theory diagram that the present invention is applicable to the digital RF far-drawing system of dual communication standard.As shown in Figure 1, the described digital RF far-drawing system of dual communication standard that is applicable to comprises that the digital fiber radio frequency zooms out frequency-selecting near-end machine (LIM, Local Interface Module, the local interface module, be called for short near-end) 10 and the digital fiber radio frequency zoom out frequency-selecting remote termination (RRH, Remote Radio Head, the far end radio frequency head is called for short far-end) 20.Described digital fiber radio frequency zooms out frequency-selecting near-end machine 10 and zooms out frequency-selecting remote termination 20 with the digital fiber radio frequency and be connected by optical fiber 66.
As Fig. 2, described digital radio frequency far-pulling frequency-selecting near-end machine 10 comprises GSM near-end frequency-variable module 101, DCS near-end frequency-variable module 102 and near-end digital intermediate frequency dish 103.Describe in detail below with reference to Fig. 4.
Described GSM near-end frequency-variable module 101 comprises low-converter 101a and upconverter 101b.Described DCS frequency-variable module 102 comprises low-converter 102a and upconverter 102b.Described near-end digital intermediate frequency dish 103 comprises all the A/D converter 103a that is connected with the low-converter 102a of the low-converter 101a of described GSM frequency-variable module 101 and described DCS frequency-variable module 102, the first digital signal processing unit 103b that is connected with A/D converter 103a, the optical transceiver 103c that is connected with the described first digital signal processing unit 103b, the second digital signal processing unit 103d that is connected with described optical transceiver 103c, the D/A converter 103e that is connected with the upconverter 102b of the upconverter 101b of described second digital signal processing unit 103d and described GSM frequency-variable module 101 and described DCS frequency-variable module 102.
With reference to figure 3, described digital radio frequency far-pulling frequency-selecting remote termination 20 comprises remote digital intermediate frequency dish 203, GRRU integrated module 201, GSM analog predistortion module (GSM APD) 204, GSM power amplifier (GSM PA) 205, GSM duplexer 206, DRRU integrated module 202, DCS analog predistortion module (DCS APD) 207, DCS power amplifier (DCS PA) 208, DCS duplexer 209.Describe in detail below with reference to Fig. 4.
Described remote digital intermediate frequency dish 203 comprises optical transceiver 203a, the first digital signal processing unit 203b that is connected with described optical transceiver 203a, the D/A converter 203c that is connected with the first digital signal processing unit 203b, the A/D converter 203d that are connected with wide transceiver 103c by optical fiber 66, is connected the second digital signal processing unit 203e with A/D converter 203d and described optical transceiver 203a.
Described GRRU integrated module 201 comprises the upconverter 201a, the low noise amplifier 201b that are connected with the D/A converter 203c of described remote digital intermediate frequency dish 203, the low-converter 201c that is connected with the A/D converter 203d of described low noise amplifier 201b and described remote digital intermediate frequency dish 203.Described GSM analog predistortion module 204 is connected with the upconverter 201a of described GRRU integrated module 201.Described GSM power amplifier 205 is connected with described GSM analog predistortion module 204.Described GSM duplexer 206 is connected with the low noise amplifier 201b of described power amplifier 205 and described GRRU integrated module 201.
Described DRRU integrated module 202 comprises the upconverter 202a, the low noise amplifier 202b that are connected with the D/A converter 203c of described remote digital intermediate frequency dish 203, the low-converter 202c that is connected with the A/D converter 203d of described low noise amplifier 202b and described remote digital intermediate frequency dish 203.Described DCS analog predistortion module 207 is connected with the upconverter 202a of described DRRU integrated module 202.Described DCS power amplifier 208 is connected with described DCS analog predistortion module 207.Described DCS duplexer 209 is connected with the low noise amplifier 202b of described DCS power amplifier 208 and described DRRU integrated module 202.
Below in conjunction with Fig. 4 the operation principle that is applicable to the digital RF far-drawing system of dual communication standard shown in Figure 1 is described, below at first illustrate that from GSM down direction, GSM up direction this digital radio frequency stretch system can support GSM standard (with reference to the solid arrow figure 2, Fig. 3), illustrate that from DCS down direction, DCS up direction this digital radio frequency stretch system can support DCS standard (with reference to the solid arrow figure 2, Fig. 3) then.
* GSM down direction
Native system is when GSM standard operating state, as Fig. 1,2,3, send into the GSM near-end frequency-variable module 101 of digital radio frequency far-pulling frequency-selecting near-end machine 10 from the GSM downlink radio-frequency signal of GSM base station main antenna by coupler, the low-converter 101a of GSM near-end frequency-variable module 101 is down-converted to intermediate-freuqncy signal with the GSM downlink radio-frequency signal.The A/D converter 103a of near-end digital intermediate frequency dish 103 carries out analog-to-digital conversion with described GSM intermediate-freuqncy signal, be transformed to the GSM digital signal, digital signal processing unit 203b arrives baseband signal with the Digital Down Convert of described GSM digital signal, and institute's baseband signal carried out digital filtering, by certain frame format filtered baseband signal is packaged into serial data.Described serial data converts light signal to via optical transceiver 103c and transfers out by optical fiber 66.
The digital intermediate frequency dish 203 that the digital fiber radio frequency zooms out frequency-selecting remote termination 20 converts described light signal to serial data by optical transceiver 203a, digital signal processing unit 203b separates frame to serial data, the baseband signal that serial data is separated behind the frame is carried out digital filtering, and with filtered baseband signal Digital Up Convert to digital signal, finish the time delay adjustment simultaneously, the digital signal after D/A converter 203c will handle reverts to intermediate-freuqncy signal.The upconverter 201a of GRRU integrated module 201 upconverts to the GSM downlink radio-frequency signal with intermediate-freuqncy signal.204 pairs of GSM downlink radio-frequency signals of GSM analog predistortion module carry out linearity adjustment.The adjusted GSM downlink radio-frequency signal of 205 pairs of linearities of GSM power amplifier amplifies.The radiofrequency signal of 206 pairs of amplifications of GSM duplexer is carried out filtering.Filtered GSM downlink radio-frequency signal is emitted to portable terminal by antenna.
* GSM up direction
Native system is when GSM standard operating state, as Fig. 1,2,3, send into the GSM duplexer 206 of digital radio frequency far-pulling frequency-selecting remote termination 20 from the up radiofrequency signal of the GSM of portable terminal by antenna, 206 pairs of up radiofrequency signals of described GSM of GSM duplexer are carried out filtering.The low noise amplifier 201b of GRRU integrated module 201 amplifies described filtered GSM radiofrequency signal, and the up radiofrequency signal of GSM after low-converter 201c will amplify is down-converted to intermediate-freuqncy signal.The A/D converter 203d of remote digital intermediate frequency dish 203 is transformed to the GSM digital signal with intermediate-freuqncy signal, digital signal processing unit 203e arrives baseband signal with the Digital Down Convert of described GSM digital signal, and described baseband signal carried out digital filtering, with the baseband signal of filtering with from networking in other digital radio frequency far-pulling frequency-selecting remote termination baseband signal close the road, by certain frame format the baseband signal of closing in the networking behind the road is packaged into serial data then, finishes uplink time delay adjustment and noise suppressed simultaneously.Described serial data transfers out by optical fiber 66 via optical transceiver 203a.
The digital signal processing unit 103d of the digital intermediate frequency dish 103 of digital radio frequency far-pulling frequency-selecting near-end machine 10 will separate frame by the serial data that optical transceiver 103c receives, and the baseband signal of separating behind the frame carried out digital filtering, and with filtered baseband signal Digital Up Convert to digital signal, the digital signal after D/A converter 103e will handle reverts to intermediate-freuqncy signal.The upconverter 101b of GSM near-end frequency-variable module 101 upconverts to the up radiofrequency signal of GSM with intermediate-freuqncy signal.Described radiofrequency signal is sent to the GSM base station by coupler.
* DCS down direction
Native system is when DCS standard operating state, as Fig. 1,2,3, send into the DCS near-end frequency-variable module 102 of digital radio frequency far-pulling frequency-selecting near-end machine 10 from the DCS downlink radio-frequency signal of DSC base station main antenna by coupler, the low-converter 102a of DCS near-end frequency-variable module 102 is down-converted to intermediate-freuqncy signal with the DCS downlink radio-frequency signal.The A/D converter 103a of digital intermediate frequency dish 103 carries out analog-to-digital conversion with described DCS intermediate-freuqncy signal, be transformed to digital signal, digital signal processing unit 103b arrives baseband signal with described digital signal Digital Down Convert, and described baseband signal carried out digital filtering, by certain frame format filtered DCS digital medium-frequency signal is packaged into serial data.Described serial data transfers out via optical transceiver 103c and by optical fiber 66.
The digital intermediate frequency dish 203 that the digital fiber radio frequency zooms out frequency-selecting remote termination 20 receives described DCS serial data by optical transceiver 203a, digital signal processing unit 203b separates frame to serial data, the baseband signal of separating behind the frame is carried out digital filtering, and with filtered baseband signal Digital Up Convert to digital signal, finish the time delay adjustment simultaneously, the digital signal after D/A converter 203c will handle reverts to intermediate-freuqncy signal.The upconverter 202a of DRRU integrated module 202 upconverts to the DCS downlink radio-frequency signal with intermediate-freuqncy signal.207 pairs of radiofrequency signals of DCS analog predistortion module are carried out linearity adjustment.208 pairs of adjusted radiofrequency signals of linearity of DCS power amplifier are amplified.The radiofrequency signal of 209 pairs of amplifications of DCS duplexer is carried out filtering.Filtered DCS downlink radio-frequency signal is emitted to portable terminal by antenna.
* DCS up direction
Native system is when DCS standard operating state, as Fig. 1,2,3, send into the DCS duplexer 209 of digital radio frequency far-pulling frequency-selecting remote termination 20 from the up radiofrequency signal of the DCS of portable terminal by antenna, 209 pairs of up radiofrequency signals of described DCS of DCS duplexer are carried out filtering.The low noise amplifier 202b of DRRU integrated module 202 amplifies described filtered DCS radiofrequency signal, and the up radiofrequency signal of DCS after low-converter 202c will amplify is down-converted to intermediate-freuqncy signal.The A/D converter 203d of remote digital intermediate frequency dish 203 is transformed to digital signal with the DCS intermediate-freuqncy signal, digital signal processing unit 203e arrives baseband signal with the digital signal Digital Down Convert, and described baseband signal carried out digital filtering, with filtered baseband signal with from networking in other digital radio frequency far-pulling frequency-selecting remote termination baseband signal close the road, by certain frame format the baseband signal of closing in the networking behind the road is packaged into serial data then, finishes uplink time delay adjustment and noise suppressed simultaneously.Described serial data transfers out via optical transceiver 203a and by optical fiber 66.
The digital signal processing unit 103d of the digital intermediate frequency dish 103 of digital radio frequency far-pulling frequency-selecting near-end machine 10 will separate frame by the serial data that optical transceiver 103c receives, and the baseband signal of separating behind the frame carried out digital filtering, to digital signal, the recovering digital data after D/A converter 103e will handle is an intermediate-freuqncy signal with filtered baseband signal Digital Up Convert.The upconverter 102b of DCS near-end frequency-variable module 102 upconverts to the up radiofrequency signal of DCS with intermediate-freuqncy signal.Described radiofrequency signal is sent to the DCS base station by coupler.
As from the foregoing, described digital radio frequency far-pulling frequency-selecting near-end machine 10 comprise a GSM near-end down link 11 that the low-converter 101a by GSM frequency-variable module 101 forms, a DCS near-end down link 12 forming by the low-converter 102a of DCS frequency-variable module 102, a GSM near-end up link 13 of forming by the upconverter 101b of GSM frequency-variable module 101, a DCS near-end up link 14 of forming by the upconverter 102b of DCS frequency-variable module 102, the near-end digital signal processing module 15 formed by near-end digital intermediate frequency dish 103.The upconverter 201a that described digital radio frequency far-pulling frequency-selecting remote termination 20 comprises by GRRU integrated module 201, GSM analog predistortion module 204, GSM power amplifier 205, the GSM far-end down link 21 that GSM duplexer 206 is formed, upconverter 202a by DRRU integrated module 202, DCS analog predistortion module 207, DCS power amplifier 208, the DCS far-end down link 22 that DCS duplexer 209 is formed, by GSM duplexer 206, the GSM far-end up link 23 that the low noise amplifier 201b of GRRU integrated module 201 and low-converter 201c form, by DCS duplexer 209, the DCS far-end up link 24 that the low noise amplifier 202b of DRRU integrated module 202 and low-converter 202c form, the remote digital signal processing module of forming by remote digital intermediate frequency dish 203 25.
Need explanation, in engineering was used, the effect of the descending input of the DCS/GSM/external coupler in up output port place of the above-mentioned digital radio frequency far-pulling frequency-selecting near-end machine of mentioning 10 was to prevent descendingly and the up link reflection that liquidates, and causes interference.This coupler uses for the engineering application scenarios, therefore is not included in the native system link.
Need illustrate, in Fig. 2,3, digital intermediate frequency dish 103 and 203 provides the intrinsic reference signal for GSM near-end frequency-variable module 101, DCS near-end frequency-variable module 102 and GRRU integrated module 201, DRRU integrated module 202, and the uplink and downlink frequency that is provided with in GSM and the DCS system link is stablized in effect.
The networking mode of the digital RF far-drawing system of dual communication standard that is applicable to shown in Figure 1 has hub-and-spoke configuration, chain structure and hybrid combination.
Showed the hub-and-spoke configuration networking mode as Fig. 5: a LIM directly is with a plurality of RRH (tentative is one drag two), according to the telephone traffic situation of overlay area, transfers the alternative base station of carrier resource automatically and carries out the absorption of telephone traffic.
Showed the daisy architecture networking mode as Fig. 6: a LIM is with a RRH, and this RRH connects next RRH again.This kind mode is specially adapted to the covering in railway, subway, tunnel etc.
Showed the hybrid combination networking mode as Fig. 7: be similar to the room light fibre distribution system, but digital form have the transmission dynamic range big, with the unrestricted substantially advantage of the number of RRH.
In the practical engineering application, the networking mode of digital RF far-drawing system adopts tree topology, and a LIM can connect 2 RRH, but RRH again 1 RRH of cascade form next jumping.LIM and RRH, or be connected with optical fiber between RRH and the RRH far-end, the single fiber bi-directional transmission means adopted according to actual conditions.
It is pointed out that and see Fig. 2 that described digital fiber radio frequency zooms out frequency-selecting near-end machine 10 and also comprises Modem 104 and near-end OMC integration module.Near-end OMC integration module is used for near-end machine 10 is realized inquiry and control that Modem 104 is used to set up the remote monitoring channel passage of digital RF far-drawing system.Modem 104 and near-end OMC integration module are formed near-end monitoring module 16.See Fig. 3, the digital fiber radio frequency zooms out frequency-selecting remote termination 20 and also comprises far-end OMC integration module, is used for remote termination 20 is realized inquiry and control, and it forms remote monitoring module 26.Specify below.
Near-end OMC integration module is integrated on the near-end digital intermediate frequency dish 103, by RS485 agreement and GSM near-end frequency-variable module 101, DCS near-end frequency-variable module 102 is connected with near-end digital intermediate frequency dish 103, be used for GSM near-end frequency-variable module 101, DCS near-end frequency-variable module 102 and near-end digital intermediate frequency dish 103 are monitored 16 system transfer of data with the RS485 agreement, comprise the setting of up-downgoing noise gate, decay control, automatic electric-level control, channel number is provided with, power output inquiry etc., and with upper strata webmaster communication, the data of gathering are sent to the upper strata webmaster, to realize the digital fiber radio frequency is zoomed out the inquiry and the control of frequency-selecting near-end machine 10.
Far-end OMC integration module is integrated on the remote digital intermediate frequency dish 203, by RS485 agreement and GRRU integrated module 201, DRRU integrated module 202, GSM power amplifier 205, DCS power amplifier 208 is connected with remote digital intermediate frequency dish 203, be used for GRRU integrated module 201, DRRU integrated module 202, GSM power amplifier 205, DCS power amplifier 208 and remote digital intermediate frequency dish 203 monitor transmit mutually with 16 system data of RS485 agreement and with upper strata webmaster communication, the data of gathering are sent to the upper strata webmaster, to realize the digital fiber radio frequency is zoomed out the inquiry and the control of frequency-selecting remote termination 20.
The digital fiber radio frequency zooms out between frequency-selecting near-end machine 10 and the near-end OMC integration module and sets up remote monitoring channel passage by near-end Modem104, make the upper strata webmaster realize the digital fiber radio frequency is zoomed out the note or the remote monitoring of PS territory of frequency-selecting near-end machine 10, other modes such as dialing, xDSL, Ethernet etc. are as alternative.But equipment is independent operating under the situation that no OMC connects.This monitoring is also zoomed out a plurality of digital fiber radio frequencies that frequency-selecting near-end machine 10 inquires about in the networking by the digital fiber radio frequency and is zoomed out frequency-selecting remote termination 20.
Be the interference to the operate as normal of other remote terminations 20 in netting that the mistake setting that prevents 20 pairs of near-end machines 10 of certain remote termination in the networking causes, each remote termination 20 has limited the function that near-end machine 10 associated arguments data are set.
Need to prove that GSM frequency-variable module 101, DCS frequency-variable module 102, near-end digital intermediate frequency dish 103, Modem104 that the digital fiber radio frequency of digital RF far-drawing system of the present invention zooms out frequency-selecting near-end machine 10 are powered by 100W power module 105.GRRU integrated module 201, DRRU integrated module 202, remote digital intermediate frequency dish 203, GSM APD 204, GSM PA 205, DCS APD 207, DCS PA 208 that the digital fiber radio frequency zooms out frequency-selecting remote termination 20 are powered by 520W power module 211.
As seen from the above, the present invention is applicable to that the advantage of digital RF far-drawing system of dual communication standard is as follows:
1, the power amplification implementation is that the peak power output of GSM power amplifier 205 in the GSM link is 25W in the native system scheme, the operating power of GSM analog predistortion module 204 is 1W, the peak power output of DCS power amplifier 208 is 25W in the DCS link, the operating power of DCS analog predistortion module 207 is 1W, this power amplification scheme can make the output of system descending direction be pushed into GSM 60W and DCS 60W, when high power work is under GSM and two kinds of communication standards of DCS, improved the in-band intermodulation and neighboring trace rejection ratio (ACPR) index of system, satisfied the requirement of market and low equipment cost integrated digital RF far-drawing system.
2, near in the native system, far-end adopts the digital fiber transmission technology, realize the mutual conversion of radiofrequency signal by near-end GSM, DCS frequency-variable module, far-end GRRU and DRRU integrated module, near-end and remote digital intermediate frequency dish and optical transceiver to light signal, signal is not decayed with the decay of light signal, in long distance and demultiplex transmission system, keep dynamic range and service mass conservation, make network design more flexible;
3, the GSM and the DCS two-way upstream noise inhibit feature that provide of the digital signal processing unit in the remote digital intermediate frequency dish 203, upstream noise to each remote terminal is controlled, greatly reduce upstream noise phase mutual interference between each remote terminal, eliminate the influence of uplink interference the base station;
4, the GSM that provides of the digital signal processing unit in the remote digital intermediate frequency dish 203 and DCS two-way time delay are adjusted function, can eliminate with overlapping covered delay dispersion between the different RRH in sector and disturb.
5, adopted advanced Digital Signal Processing and digital signal optical fiber transmission technique in the digital intermediate frequency dish of near in the native system, far-end, realized that the signal of the long-distance transmissions of multi-carrier mobile communication signal and big capacity, great dynamic range covers.
6, near, the far-end support double-standard of native system.Power height, the noise of 24 frequency adaptive frequency-selectings and above-mentioned 5 embodiments are low in two nets that digital signal processing unit in near-end digital intermediate frequency dish 103 and the remote digital intermediate frequency dish 203 and OMC integration module program provide, transmission range is long, the advantage of networking flexibility, and bigger advantage is arranged in practical engineering application.It is compared with DCS single system digital RF far-drawing system with 2 GSM are installed simultaneously, can reduce installing space to greatest extent, reduces equipment cost.Simultaneously, near, the integrated OMC of remote digital intermediate frequency dish have perfect self-checking alarming function and monitoring function in the system.
Above invention has been described in conjunction with most preferred embodiment, but the present invention is not limited to the embodiment of above announcement, and should contain various modification, equivalent combinations of carrying out according to essence of the present invention.