KR20090032863A - Microwave relaying apparatus for synchronizing using pilot signal in mobile communication system and method thereof - Google Patents

Abstract

A microwave relaying apparatus for synchronizing by using a pilot signal in a mobile communication system and a method thereof are provided to synchronize between the microwave relaying apparatuses to perform communication, thereby enabling a mobile terminal to smoothly transceive a service signal with a base station. A microwave relay apparatus comprises a mixer(112), a pilot PLL(Phase-Locked Loop)(114) and a synthesizer(115). A wireless communication service signal generated based on a synthesized signal is transmitted to another relay apparatus. The pilot signal is inserted within the bandwidth of an input channel signal. The pilot signal is extracted from another relay apparatus so that the pilot signal is used for production of an oscillation signal for recovering the input channel signal.

Description

Microwave relay and method for synchronizing using pilot signal in mobile communication system TECHNICAL FIELD

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base station repeater for mobile communication, and in particular, to synchronize between microwave repeaters using a pilot signal inserted into a mobile communication channel according to the standards of CDMA, PCS, WCDMA, GSM, and the like. The present invention relates to a microwave repeater for mobile communication and a method for allowing a mobile terminal to communicate with a base station to communicate with a base station.

Microwave repeaters used to operate networks such as CDMA, PCS, WCDMA, GSM, etc., unlike optical repeaters, the link section is wirelessly connected through a microwave antenna to synchronize with a remote repeater. Use a reference oscillator that is the basis of the system. Since the performance of the reference oscillator for microwave repeaters affects the system, it must be resistant to phase noise and have good frequency stability.

The microwave repeater converts base station signals according to the standards of CDMA, PCS, WCDMA, etc. into microwave bands, for example, 11 GHz or 18 GHz, using a reference oscillator and transmits them to a remote repeater through a microwave antenna. The remote repeater may be received by the microwave antenna and converted into a signal having a frequency according to the original CDMA, PCS, WCDMA, etc. service to the mobile terminal.

Current mobile communication uses high speed data services such as quadrature phase shift keying (QPSK) modulation and high speed downlink packet access (HSDPA) .If the repeater of the base station and the remote repeater are not synchronized with each other, Therefore, it is difficult to provide a smooth service to the mobile terminal.

In general, as a reference oscillator for a remote microwave repeater used to synchronize with a base station repeater, a device for generating a 10 MHz oscillation signal using a global positioning system (GPS) may be used, or a frequency shift keying (FSK) modem. An apparatus for generating a 10 MHz oscillation signal using the data transmitted from may be used. However, these oscillators have a disadvantage that they are expensive devices, and in particular, when the FSK modem is used, there is a problem in that synchronization is not achieved at the remote repeater when the received data is abnormal.

Accordingly, an object of the present invention is to solve the above-mentioned problems, an object of the present invention is to provide a mobile communication microwave repeater and a method for providing a mobile communication service by synchronizing between a base station and a remote site in a low cost and excellent performance method. To provide.

In addition, another object of the present invention is to insert a mobile communication channel according to the carrier standards, such as CDMA, PCS, WCDMA, GSM, so that the mobile terminal can receive a smooth service even if the remote repeater does not have to install an expensive reference oscillator The present invention relates to a microwave repeater for mobile communication and a method for synchronizing communication using a pilot signal.

First, to summarize the features of the present invention, the microwave repeater for transmitting a communication service signal to another repeater according to an aspect of the present invention for achieving the object of the present invention, a mixer for converting the frequency of the input channel signal ; A pilot PLL for converting a frequency of the input reference oscillation signal to generate a pilot signal; And a synthesizer for synthesizing the pilot signal and the frequency-converted signal by the mixer, wherein a wireless communication service signal generated based on the synthesized signal is transmitted to the other repeater, and the pilot signal is input to the input channel. It is inserted in the bandwidth of the signal, it is extracted from the other repeater is characterized in that it is used to generate an oscillation signal for the recovery of the input channel signal.

The microwave repeater is connected to a base station to receive a base station signal according to at least one of the standards of CDMA, PCS, WCDMA, and GSM as the input channel signal, and wirelessly links the other repeater to the other repeater for the wireless And a communication service signal.

And the pilot signal is inserted into a high or low band within the bandwidth excluding a band occupied by the input channel signal from a center frequency to both sides.

In addition, the microwave repeater for receiving a communication service signal from another repeater according to another aspect of the present invention, the frequency converter for converting the frequency of the wireless communication service signal of a predetermined bandwidth; And separating a pilot signal inserted at a predetermined frequency within the bandwidth from the signal frequency-converted by the frequency converter, generating a synchronization oscillation signal based on the pilot signal, and using the synchronization oscillation signal. And a remote unit for converting a frequency of the first signal from which the pilot signal has been removed from the signal frequency-converted by the frequency converting unit, wherein the frequency converting unit uses the synchronization oscillation signal for the frequency of the wireless communication service signal. It characterized in that the conversion.

The remote unit includes a divider for converting a frequency of the pilot signal to provide a circuit for generating the synchronization oscillation signal.

The divider includes: a PLL for generating an oscillation signal having a predetermined frequency synchronized with the synchronization oscillation signal; And a mixer for converting the frequency of the signal whose pilot signal is filtered by at least one SAW filter using the PLL output.

The divider may convert a frequency of the pilot signal using at least one SAW filter and at least one frequency divider.

The remote unit includes a synchronization PLL for generating the synchronization oscillation signal from a signal whose frequency of the pilot signal is converted.

The synchronization PLL may include: an R counter for counting a signal obtained by converting a frequency of the pilot signal and converting a frequency; A prescaler for pre-scaling the frequency of the feedback signal; An N counter that counts an output of the prescaler and converts a frequency; A phase detector for comparing the phase between the output of the R counter and the output of the N counter; A charge pump adjusting an output current according to a comparison result of the phase detector; A loop filter generating a signal corresponding to a predetermined DC according to the output of the charge pump; And an oscillation circuit generating the synchronization oscillation signal in response to an output voltage of the loop filter.

The remote unit includes an oscillator for generating an oscillation signal having the same frequency as the synchronization oscillation signal; And an RF switch for selectively selecting an output of the synchronization PLL or an output of an oscillator according to a predetermined control signal.

The remote unit converts the first signal into a second signal having an intermediate frequency using the synchronization oscillation signal, and then converts the frequency of the second signal using the synchronization oscillation signal to convert the original channel signal. It is characterized by restoring.

In addition, according to another aspect of the present invention, a method for transmitting a microwave communication service signal to a repeater for mobile communication comprises the steps of: converting a frequency of an input channel signal; Generating a pilot signal by converting a frequency of the input reference oscillating signal; And synthesizing the frequency-converted signal and the pilot signal, wherein a wireless communication service signal generated based on the synthesized signal is transmitted to the repeater for mobile communication, wherein the pilot signal is connected to the input channel signal. It is inserted in the bandwidth, and is extracted from the mobile communication repeater is used for generating an oscillation signal for the recovery of the input channel signal.

In addition, according to another aspect of the present invention, a method for receiving a microwave communication service signal from a mobile communication repeater includes: converting a frequency of a wireless communication service signal having a predetermined bandwidth; And separating the pilot signal inserted at a predetermined frequency within the bandwidth from the frequency converted signal. Generating a synchronization oscillation signal based on the pilot signal; Converting a frequency of a signal from which the pilot signal has been removed from the frequency-converted signal using the synchronization oscillation signal, and converting a frequency of the wireless communication service signal using the synchronization oscillation signal Do it.

According to the microwave repeater according to the present invention, it is possible to provide a mobile communication service by synchronizing between a base station and a remote site in a low cost and excellent performance method.

In addition, according to the microwave repeater according to the present invention, a synchronization service is generated using an oscillation signal generated based on a pilot signal inserted into a mobile communication channel according to a carrier standard such as CDMA, PCS, WCDMA, GSM, and a communication service between a base station and a remote site. By transmitting and receiving a signal, a mobile terminal can be provided with a smooth mobile communication service even if a remote reference does not have an expensive reference oscillator.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings and the contents described in the accompanying drawings, but the present invention is not limited or limited to the embodiments. Like reference numerals in the drawings denote like elements.

1 is a view for explaining a mobile communication relay system 100 including a base station repeater and a remote repeater according to an embodiment of the present invention. Referring to FIG. 1, the base station repeater according to an embodiment of the present invention includes an IDU (Indoor Donor Unit) 110 and a MDU (Microwave Donor Unit) 120. The remote repeater according to an embodiment of the present invention includes a Microwave Remote Unit (MRU) 130 and a Remote Unit (Remote Unit) 140.

The IDU 110 performs frequency conversion (eg, center frequency) on channel signals (eg, center frequency 2.16 GHz) generated for service from a base station of a wireless network such as CDMA, PCS, WCDMA, and GSM to a mobile terminal. 1.44 GHz) to the MDU 120, and the MDU 120 carries the channel signal received from the IDU 110 in a radio frequency (RF) frequency band (for example, a center frequency of 11 GHz) and wirelessly communicates through an antenna. It is sent as a service signal. The reverse signal is processed in the reverse of the forward signal processing. For example, signals or control signals generated from a mobile terminal may be transmitted as a radio communication service signal through an antenna in a remote MRU 130, where the MDU 120 frequency downs the radio communication service signal to generate an IDU 110. The IDU 110 transmits the signal received from the MDU 120 to the base station by frequency conversion.

The remote RU 140 converts a radio signal (for example, a center frequency of 2.16 GHz) from the mobile terminal to the MRU 130 by frequency conversion, and the MRU 130 receives the radio communication service signal through an antenna. In addition to sending the data to the MDU 120, the MRU 130 receives a wireless communication service signal received from the MDU 120 and performs frequency conversion (for example, a center frequency of 1.44 GHz) to forward the RU ( 140, and the RU 140 loads the channel signal received from the MRU 130 in a radio frequency band (for example, a center frequency of 2.16 GHz) for service to the mobile terminal and transmits it through an antenna.

As described above, the mobile communication relay system 100 not only processes and transmits a base station signal to a mobile terminal for forward processing of a downlink, but also processes a signal from a mobile terminal for reverse processing of an uplink and transmits the signal to a base station in a wireless network. do.

Hereinafter, the mobile communication relay system 100 will be described with reference to a process of performing forward processing. However, the present invention is not limited thereto, and since a forward signal processing process is similar to a reverse signal processing process, a necessary process of the forward signal processing process may be applied to the reverse process even in the reverse signal processing.

As shown in FIG. 2, a base station signal may be allocated and transmitted as a plurality of frequency allocations within one channel having a 20 MHz bandwidth, and multiple signals of channels having the same bandwidth may be processed in parallel. Each FA signal may be transmitted from the RU 140 to each sector via an antenna, for example a four sector antenna. In the case of an omni antenna, one channel having a 20 MHz bandwidth is not allocated to multiple FAs, and a signal of a channel unit band may be transmitted in all directions toward the mobile terminal through the omni antenna.

In particular, in the present invention, the pilot signal PILOT is inserted in each channel in the IDU 110 and transmitted to the remote location, and the pilot signal PILOT is extracted from the remote RU 140 and used for synchronization. Accordingly, it is possible to provide a mobile communication service by synchronizing in an effective and excellent manner without using an expensive global positioning system (GPS) or a frequency shift keying (FSK) modem at a remote location.

3 is a view for explaining the IDU 110 of FIG. Referring to FIG. 3, the IDU 110 includes a first amplifier (AMP # 1) 111, a mixer 112, an oscillator 113, a pilot phase-locked loop (PLL) 114, and a synthesizer ( 115, a second amplifier (AMP # 2) 116, and a bias-T 117.

 The first amplifier (AMP # 1) 111 amplifies the channel signal transmitted from the base station at a voltage level suitable for signal processing in the IDU 110. The base station signal may be a signal of a predetermined channel (for example, center frequency 2.16 GHz, bandwidth 20 MHz) according to standards such as CDMA, PCS, WCDMA, and GSM for transmission to a mobile terminal.

The mixer 112 converts the frequency of the amplified channel signal by combining the frequency of the channel signal amplified by the first amplifier (AMP # 1) 111 and the oscillation signal having a predetermined frequency output from the oscillator 113. The oscillator 113 receives a 10 MHz signal from an oscillation device capable of generating a 10 MHz reference oscillation signal stably in processing a base station signal such as a 10 MHz oscillation circuit using a GPS or an Oven Compensated Crystal Oscillator (OCXO) used in a base station, and receives a frequency at an appropriate frequency. Generate an increased oscillation signal.

The pilot PLL 114 generates a pilot signal PILOT having an increased frequency using the 10 MHz reference oscillation signal as described above. The pilot signal PILOT is, for example, a signal of 1449.9 MHz as shown in FIG. 2, and is inserted into a bandwidth (for example, 20 MHz) of the channel signal. It is inserted at a position 680 kHz away from the actual channel signal, for example, at a higher or lower edge of the band except for the band (e.g., 18.44 MHz). As shown in FIG. 2, a link frequency shift keying (FSK) signal for establishing a data communication path by wireless linking with a counterpart microwave repeater may be inserted at an opposite side of the pilot signal PILOT. As described below, the pilot signal PILOT is extracted from the RU 140 in the relative microwave repeater and used to generate an oscillation signal for restoring the channel signal.

The synthesizer 115 synthesizes the signal frequency-converted by the mixer 112 and the pilot signal PILOT. The synthesizer 115 may use the 10MHz reference oscillation signal as described above. According to the frequency synthesis of the mixer 112 and the synthesizer 115, a signal having a target frequency, for example, a center frequency of 1.44 GHz including a channel signal and a pilot signal (PILOT) is generated, which is transmitted to the MDU 120. Appropriately amplified in the second amplifier (AMP # 2) 116 as appropriate and a suitable level of DC (eg, 27 volts) is added by the bias-tee 117.

The output signal of the bias-tee 117 is transmitted to the MDU 120, the MDU 120 receives a signal containing the channel signal and pilot signal (PILOT) received from the IDU (110) RF frequency band (for example And transmits it as a wireless communication service signal through an antenna at a center frequency of 11 GHz). The MDU 120 includes a multiplexer, a control circuit, a power amplifier, a diplexer, and the like, and signals of various channels (eg, a center frequency of 10.715 GHz, 10.735 GHz, etc.) received from the IDU 110. ) Is converted to the corresponding RF frequency band and transmitted to the MRU 130, and processed and transmitted to the IDU 110 by microwave in the reverse direction received from the MRU 130.

As such, when the MDU 120 wirelessly links with the counterpart microwave repeater and transmits the radio communication service signal to the MRU 130 in the counterpart microwave repeater, the MRU 130 receives the radio communication service signal received from the MDU 120. (For example, the center frequency 11 GHz) is received, the frequency conversion (for example, the center frequency 1.44 GHz) is transmitted to the RU 140, and the RU 140 transmits the channel signal received from the MRU 130 to the mobile terminal. The radio frequency band (for example, the center frequency 2.16GHz) for the furnace service is transmitted through an antenna.

4 is a diagram for describing the MRU 130 and the RU 140 of FIG. 1.

Referring to FIG. 4, the MRU 130 includes a frequency converter including a first mixer 131 and a first PLL 132, and the RU 140 includes a first divider 141 and a divider 142. , A synchronization unit 143, a second distributor 144, a second mixer 145, a second PLL 146, a third mixer 147, and a third PLL 148.

Although not shown in FIG. 4, the MRU 130 receives a wireless communication service signal from the MDU 120, processes the signal from the RU 140, and transmits the signal to the MDU 120 to the MDU 120. Similarly, the MDU 120 includes a multiplexer, a control circuit, a power amplifier, a diplexer, and the like, and converts signals of various channels (for example, 23 channels) received from the RU 140 into corresponding RF frequency bands. In addition to transmitting to the MRU (120), the processing of the microwave received from the MDU 120 and forwards to the RU (140).

The first PLL 132 of the MRU 130 receives the synchronization oscillation signal (eg, 10 MHz) generated by the synchronizer 143 using the pilot signal PILOT through the second divider 144. Generate an oscillation signal of constant frequency. Accordingly, the first mixer 131 of the MRU 130 is a frequency of a wireless communication service signal (for example, center frequency 11 GHz) of a predetermined bandwidth (for example, 20 MHz per channel) from the MDU 120 extracted at the front end. Is down-converted (for example, to 1.44 GHz) using the oscillation signal generated by the first PLL 132. When the RU 140 is not a problem of signal distortion at a short distance from the MRU 130, the first mixer 131 and the first PLL 132 may be included in the RU 140, where 1 The front end of the mixer 131 may include a bias-tee circuit for adjusting the DC level of the received signal. Alternatively, when the signal distortion may be a problem at a long distance from the MRU 130, the first mixer 131 and the first PLL 132 may be included in the MRU 130. It is also possible that the output of one PLL 132 is sent to RU 140 after the DC level is adjusted by the bias-tee circuit.

The RU 140 may select a corresponding bandwidth (eg For example, the pilot signal PILOT inserted at a predetermined frequency is separated within 20 MHz per channel, and a synchronization oscillation signal (eg, 10 MHz) is generated based on the pilot signal PILOT. Using the synchronization oscillation signal (eg, 10 MHz) generated as described above, the RU 140 removes the pilot signal PILOT from the signal frequency-converted by the first mixer 131 and the first PLL 132. Frequency conversion of the pure channel signal is restored to a signal (for example, 2.16 GHz) to be transmitted to the mobile terminal.

To this end, the first divider 141 is within a corresponding bandwidth (eg, 20 MHz per channel) from a signal (eg, 1.44 GHz) frequency converted by the first mixer 131 and the first PLL 132. The pilot signal PILOT inserted at a predetermined frequency is separated, the pilot signal PILOT is output to the divider 142, and the pure channel signal (first mixer 131 and first PLL 132) to be subsequently processed. The signal from which the pilot signal is removed from the frequency-converted signal) is output to the second mixer 145.

The divider 142 converts a frequency (eg, 1449.9 MHz) of the pilot signal PILOT and provides, for example, an 8.95 MHz signal to the synchronizer 143.

The synchronizer 143 generates a synchronization oscillation signal (for example, 10 MHz). As shown in FIG. 4, the synchronization unit 143 uses a synchronization PLL 410 to generate a synchronization oscillation signal (for example, a signal obtained by converting an output signal of the frequency divider 142, that is, a frequency of a pilot signal PILOT). , 10 MHz), or a synchronization oscillation signal (eg, 10 MHz) may be generated using a predetermined TCXO (Temperature Compensated Crystal Oscillator) oscillator. By applying a predetermined control signal to the RF switch 420 according to the purpose, the output of the synchronous PLL 410 or the predetermined TCXO can be selected and used for synchronization.

The second divider 144 distributes the synchronization oscillation signal (eg, 10 MHz) output from the RF switch 420 to each of the first PLL 132, the second PLL 146, and the third PLL 148. do. Each of the first PLL 132, the second PLL 146, and the third PLL 148 uses an oscillation oscillation signal (eg, 10 MHz) at each position to generate an oscillation signal of a predetermined target frequency corresponding to the purpose. Create

Accordingly, the second mixer 145 uses the output oscillation signal of the second PLL 146 to transmit the pure channel signals (the first mixer 131 and the first PLL 132) output from the first distributor 141. In this case, the signal from which the pilot signal is removed from the frequency-converted signal is converted into a signal having an intermediate frequency (for example, 65 MHz). Accordingly, the third mixer 147 frequency converts the signal converted into the intermediate frequency in the second mixer 145 using the output oscillation signal of the third PLL 147 to transmit the original channel signal (eg, to be transmitted to the mobile terminal). For example, to 2.16GHz). As described above, the pure channel signal output from the first divider 141 (the signal from which the pilot signal is removed from the signal frequency-converted by the first mixer 131 and the first PLL 132) and the second mixer 145 and the second mixer 145 are output. It is also possible to use two frequency synthesis by the third mixer 147, but the second mixer 145 and the second without the third mixer 147 and the third PLL 147 as necessary, such as when the signal distortion is not severe. The mobile terminal transmits a pure channel signal (a signal from which a pilot signal is removed from a signal frequency-converted by the first mixer 131 and the first PLL 132) directly output from the first distributor 141 using the PLL 146. It can also be restored to the original channel signal (for example, 2.16 GHz) to be transmitted.

FIG. 5 is a diagram for explaining an example of the frequency divider 142 of FIG. 4. Referring to FIG. 5, the divider 142 may include a first surface acoustic wave (SAW) filter 510, a mixer 520, a PLL 530, and a second SAW filter 540. have.

The first SAW filter 510 receives the pilot signal PILOT separated by the first divider 141 and performs filtering to pass the corresponding band 1449.9 MHz and remove the other band. The PLL 530 generates an oscillation signal of a predetermined frequency synchronized with the synchronization oscillation signal (for example, 10 MHz) generated by the synchronization unit 143.

Accordingly, the mixer 520 converts the frequency of the signal from which the pilot signal PILOT is filtered by the first SAW filter 510 using the PLL 530 output, for example, into an 8.95 MHz signal. The second SAW filter 540 may again band pass filter the output of the mixer 520, and the output of the second SAW filter 540 may be output to the synchronization PLL 410.

6 is a diagram for describing another example of the divider 142 of FIG. 4. Referring to FIG. 6, the divider 142 converts a frequency of a pilot signal PILOT using at least one SAW filter 610, 630, 660 and at least one frequency divider 620, 640, 650. It can be provided to the synchronization PLL (410).

For example, the first SAW filter 610 receives the pilot signal PILOT separated from the first divider 141 and performs filtering to pass the corresponding band 1449.9 MHz and remove other bands. The first frequency divider 620 generates a signal having a frequency obtained by dividing the frequency of the output of the first SAW filter 610 by two. The output of the first frequency divider 620 is band pass filtered again by the second SAW filter 630, and then the frequency is divided by 9 in the second frequency divider 640 and the third frequency divider 650, respectively. A frequency down signal can be generated. For example, the 1449.9 MHz / 2/9/9 = 8.95 MHz signal output from the third frequency divider 650 is once again band pass filtered by the third SAW filter 660 to synchronize the PLL 410. It may be provided as.

FIG. 7 is a diagram for describing the synchronization PLL 410 of FIG. 4. Referring to FIG. 7, the synchronization PLL 410 which generates a synchronization oscillation signal (eg, 10 MHz) from a signal whose frequency of the pilot signal PILOT is converted in the divider 142 is an R counter 411. , Pre-scaler 412, N counter 413, phase detector 414, charge pump 415, loop filter 416, and Voltage Controlled Temperature Compensated Crystal Oscillator).

VCTCXO oscillation by selecting the division ratio (e.g. 716) of the R counter 411, the division ratio 8 of the prescaler, and the division ratio 800 of the N counter 413 in the synchronization PLL 410, respectively. It is possible to generate a synchronization oscillation signal of a target frequency, for example 10 MHz, from the circuit.

The R counter 411 counts pulses of a signal inputted from the frequency divider 142 (a signal whose frequency of the pilot signal is converted) (OSCIN), divides the frequency by 716, and converts the down signal, for example, 12.5 KHz. Generate a signal. The prescaler 412 performs pre-scaling to down convert the frequency of the feedback signal output from the VCTCXO oscillator by eight division. The N counter 413 counts the pulses of the output of the prescaler 412, divides the frequency by 800, and generates a down-converted signal.

Accordingly, the phase detector 414 compares the phase between the output of the R counter 411 and the output of the N counter 413 to generate a signal corresponding to the phase difference. The charge pump 415 generates a signal for adjusting the output current according to the signal corresponding to the comparison difference output from the phase detector 414. The loop filter 416 generates a signal corresponding to a direct current (DC) voltage corresponding to the output of the charge pump 415.

Accordingly, the VCTCXO oscillator circuit generates a synchronous oscillation signal (eg, 10 MHz) in response to the output voltage of the loop filter 416. The VCTCXO oscillator circuit performs a temperature compensation function and generates an oscillation signal corresponding to an input voltage. The VCTCXO oscillator circuit generates a signal having a predetermined frequency, for example, 10 MHz, according to the output of the phase detector 414. .

The functions used in the methods and systems disclosed herein may be embodied as computer readable code on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, hard disk, removable storage, and also carrier wave (for example, transmission over the Internet). It also includes the implementation in the form of. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

As described above, the present invention has been described by way of limited embodiments and drawings, but the present invention is not limited to the above embodiments, and those skilled in the art to which the present invention pertains various modifications and variations from such descriptions. This is possible. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the claims below but also by the equivalents of the claims.

1 is a view for explaining a mobile communication relay system including a base station repeater and a remote repeater according to an embodiment of the present invention.

FIG. 2 is a diagram for describing an output signal of each element of FIG. 1.

FIG. 3 is a diagram for describing an IDU (Indoor Donor Unit) of FIG. 1.

FIG. 4 is a diagram illustrating a microwave remote unit (MRU) and a remote unit (RU) of FIG. 1.

FIG. 5 is a diagram for explaining an example of the frequency divider of FIG. 4.

FIG. 6 is a diagram for describing another example of the divider of FIG. 4.

FIG. 7 is a diagram for describing a synchronization PLL of FIG. 4.

Claims (13)

In a microwave repeater for transmitting a communication service signal to another repeater, A mixer for converting a frequency of an input channel signal; A pilot PLL for converting a frequency of the input reference oscillation signal to generate a pilot signal; And A synthesizer for synthesizing the pilot signal and the frequency-converted signal by the mixer, A wireless communication service signal generated based on the synthesized signal is transmitted to the other repeater, And the pilot signal is inserted in a bandwidth of the input channel signal and extracted by the other repeater and used to generate an oscillation signal for restoring the input channel signal. The method of claim 1, wherein the microwave repeater, Connected to a base station to receive a base station signal according to at least one of CDMA, PCS, WCDMA, and GSM as the input channel signal, and wirelessly link with the other repeater to transmit the wireless communication service signal to the other repeater; Microwave repeater, characterized in that. The method of claim 1, wherein the pilot signal, The microwave repeater, characterized in that inserted into the high or low band in the bandwidth except the band occupied by the input channel signal from both sides of the center frequency. In the microwave repeater for receiving a communication service signal from another repeater, A frequency converter for converting a frequency of a wireless communication service signal having a predetermined bandwidth; And Separating a pilot signal inserted at a predetermined frequency within the bandwidth from the signal frequency-converted by the frequency converter, generates a synchronization oscillation signal based on the pilot signal, and by using the synchronization oscillation signal A remote unit converting the frequency of the first signal from which the pilot signal has been removed from the frequency converted signal; And the frequency converter converts the frequency of the wireless communication service signal using the synchronization oscillation signal. The method of claim 4, wherein the remote unit, And a divider for converting a frequency of the pilot signal to a circuit for generating the synchronization oscillation signal. The method of claim 5, wherein the divider, A PLL for generating an oscillation signal of a predetermined frequency synchronized with the synchronization oscillation signal; And And a mixer for converting the frequency of the signal whose pilot signal is filtered by at least one SAW filter using the PLL output. The method of claim 5, wherein the divider, The microwave repeater for converting the frequency of the pilot signal using at least one SAW filter and at least one frequency divider. The method of claim 4, wherein the remote unit, And a synchronization PLL for generating the synchronization oscillation signal from a signal whose frequency of the pilot signal is converted. The method of claim 8, wherein the PLL for synchronization, An R counter for counting the converted signal of the pilot signal and converting the frequency; A prescaler for pre-scaling the frequency of the feedback signal; An N counter that counts an output of the prescaler and converts a frequency; A phase detector for comparing the phase between the output of the R counter and the output of the N counter; A charge pump adjusting an output current according to a comparison result of the phase detector; A loop filter generating a signal corresponding to a predetermined DC according to the output of the charge pump; And An oscillator circuit for generating the synchronous oscillation signal in response to an output voltage of the loop filter Microwave repeater comprising a. The method of claim 4, wherein the remote unit, An oscillator for generating an oscillation signal of the same frequency as the synchronization oscillation signal; And RF switch for selectively selecting the output of the synchronization PLL or the output of the oscillator according to a predetermined control signal Microwave repeater, characterized in that it further comprises. The method of claim 4, wherein the remote unit, Converting the first signal into a second signal having an intermediate frequency using the synchronization oscillation signal, and converting the frequency of the second signal using the synchronization oscillation signal to restore an original channel signal. Microwave repeater. In the method for transmitting a microwave communication service signal to a mobile communication repeater, Converting a frequency of the input channel signal; Generating a pilot signal by converting a frequency of the input reference oscillating signal; And Synthesizing the frequency converted signal and the pilot signal, The wireless communication service signal generated based on the synthesized signal is transmitted to the repeater for mobile communication, The pilot signal is inserted into the bandwidth of the input channel signal, the communication service signal transmission method, characterized in that extracted from the repeater for mobile communication to generate an oscillation signal for the recovery of the input channel signal. In the method for receiving a microwave communication service signal from a mobile communication repeater, Converting a frequency of a wireless communication service signal of a predetermined bandwidth received; And Separating a pilot signal inserted at a predetermined frequency within the bandwidth from the frequency converted signal; Generating a synchronization oscillation signal based on the pilot signal; Converting the frequency of the signal from which the pilot signal has been removed from the frequency converted signal by using the synchronization oscillation signal; And converting a frequency of the wireless communication service signal using the synchronization oscillation signal.

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