KR20080098868A - Method and apparatus for transforming and relaying radios frequency - Google Patents

Abstract

A method for converting/relaying a frequency and an apparatus therefor are provided to reduce the cost required when operating and installing a time-sharing wireless communication service such as the Wibro service. A method for converting/relaying a frequency of a time-sharing wireless communications service comprises following steps of: converting the reference frequency, which is the frequency of a signal received from a base station or an optical repeater, into an idle frequency, which is not currently used by the base station(S202); transmitting the signal with the converted idle frequency(S206); converting the frequency of the received signal into the reference frequency(S208); and transmitting the signal with the converted reference frequency to a mobile station(S212).

Description

Frequency transform relay method and apparatus {Method and apparatus for transforming and relaying radios frequency}

1 is a diagram illustrating a frequency conversion relay service system in which a frequency conversion relay apparatus according to the present invention can be used.

2 is a flowchart illustrating a procedure of performing downlink in the frequency conversion relay method according to an embodiment of the present invention.

3 is a flowchart illustrating a sequence of performing uplink in a frequency conversion relay method according to an embodiment of the present invention.

Figure 4 is a block diagram showing the configuration of the DU of the frequency conversion relay apparatus according to an embodiment of the present invention.

5 is a configuration diagram showing the configuration of the RU of the frequency conversion relay apparatus according to an embodiment of the present invention.

Figure 6 is a block diagram illustrating the configuration of a frequency conversion relay apparatus according to an embodiment of the present invention.

7 is a block diagram of a conventional digital optical repeater that can be included in the frequency conversion repeater according to the present invention.

8 is a configuration diagram in which the frequency converter according to the present invention is coupled to a main hub of a conventional digital optical repeater.

9 is a configuration diagram in which the frequency converter according to the present invention is coupled to a remote unit of a conventional digital optical repeater.

The present invention relates to a frequency conversion relay method and apparatus, and more particularly, to a frequency conversion relay method and apparatus that can be used in a time division wireless communication service such as a WiBro (Wireless Broadband) service.

Recently, various wireless communication services have emerged, such as a wireless broadband service, which is a portable Internet service that enables high-speed wireless Internet service at a low rate, and a mobile communication service that enables video calls.

WiBro is an abbreviation of Wireless Broadband and is one of the representative wireless portable Internet services, and is a time division duplex (TDD) type wireless communication service.

The WiBro service uses a TDD (Time Division Duplex) scheme as described above, and uses an Orthogonal Frequency Division Multiplexing (OFDM) scheme as a modulation scheme.

The TDD scheme is a bidirectional transmission scheme in which uplinks and downlinks are alternately assigned in time in the same frequency band, and is more efficient than the frequency division duplex (FDD) scheme in which two different frequencies are allocated to the uplink and the downlink. This high, time slot dynamic allocation makes it ideal for asymmetric or bursty application transfers.

In addition, the OFDM scheme is a digital modulation scheme for improving transmission rate per bandwidth and preventing multipath interference. Since the OFDM scheme has orthogonality between subcarriers, the OFDM scheme may have excellent characteristics in multipath fading.

In the OFDM-TDD type WiBro system, the same frequency is used for transmission of the downlink and uplink signals, and since a time interval is divided to distinguish the downlink signal from the uplink signal, a duplexer is used for signal separation. Can't.

Accordingly, a repeater using a TDD scheme may use a switch to distinguish a downlink signal from an uplink signal and selectively provide a path for each signal. For this purpose, it is important to secure synchronization between the base station and the repeater.

On the other hand, it is very important to secure an area in which wireless communication is economically possible for wireless communication providers. In addition, wireless communication providers such as mobile communication providers require technologies and apparatuses capable of providing the same quality as the base station at a lower cost than in the base station in areas where communication communication volume is small.

To this end, devices such as optical repeaters, microwave repeaters, and channel conversion repeaters have been developed in existing mobile communication networks.

First, since the optical repeater provides an equivalent quality compared to the base station and the cost is about 1/10 of the base station, the number of domestic operators is currently operating three to four times the number of base stations.

However, the cost of the optical cable rental is a big burden due to the excessive use of the optical repeater.

On the other hand, the microwave repeater using high frequency microwave as the link frequency has no advantage of leased line cost and does not generate oscillation that appears in the on frequency RF repeater.

However, due to the requirement that a line of sight be maintained between the base station and the repeater, it is not suitable for Korea's terrain and has not been operated.

Since the channel conversion repeater uses a channel that is not used in the carrier's band as a link channel, there is no leased line cost, no oscillation, and the optical repeater does not have to apply the strict Line of Sight standard compared to the microwave. However, some problems with the channel conversion repeater can be solved.

However, the DU (Donor Unit) converts the service channel band signal of the base station and the optical repeater into the link channel band signal, and the RU (Remote Unit) serving the shaded area by converting the link channel band signal back to the service channel band signal outdoors. Because of the installation, there is a problem that twice the installation cost and operating cost are added to the RF repeater in operation and installation.

On-frequency RF repeater has the advantage of easy installation and economical, but if the isolation (isolation) between the base station opposing antenna and the mobile station opposing antenna is not secured, there is a problem that seriously affects the quality of the network by self oscillation. As a result, it is used to service underground shaded areas rather than outdoors.

On the other hand, even in time-division wireless communication services such as Wibro service, it is required to secure an economical network construction not only in the downtown but also in the suburbs where traffic is low in order to expand coverage.

In order to solve the above-mentioned problems, the coverage of the wireless communication service can be extended not only to the urban center but also to the low traffic such as the suburban area even in the time division wireless communication service such as the Wibro service. The present invention proposes a frequency conversion relay method and apparatus.

In addition, the present invention is to propose a frequency conversion relay method and apparatus that can reduce the operation and installation cost of the wireless communication service while expanding the coverage of the wireless communication service in a time division wireless communication service such as Wibro service.

Still other objects of the present invention will be readily understood through the following description of the embodiments.

In order to achieve the above object, according to an aspect of the present invention there is provided a frequency conversion relay method.

According to a preferred embodiment of the present invention, in a frequency conversion relay method of a time division wireless communication service, an idle frequency that is a frequency at which the base station does not currently use a reference frequency which is a frequency of a signal received from a base station or an optical repeater. Converting to (a); (B) transmitting the signal on the converted idle frequency; (C) reducing the frequency of the received signal to the reference frequency; And (d) transmitting the signal to the mobile station at the reduced reference frequency.

According to another preferred embodiment of the present invention, in a frequency conversion relay method of a time division wireless communication service, converting a reference frequency, which is a frequency of a signal received from a mobile station, into an idle frequency, which is a frequency not currently used by a base station. Step (a); (B) transmitting the signal on the converted idle frequency; (C) reducing the frequency of the received signal to the reference frequency; And (d) transmitting the signal to a base station or an optical repeater at the reduced reference frequency.

Each of the steps (a) may be performed after filtering and amplifying the received signal.

Each of the steps (b) may be performed by amplifying the signal with the converted idle frequency.

Each of the steps (c) may be performed after filtering and amplifying the received signal.

Each of the steps (d) may be performed in synchronization with the time at which the step (a) is performed.

According to another aspect of the present invention, a frequency conversion relay apparatus is provided.

According to a preferred embodiment of the present invention, in a frequency conversion relay apparatus of a time division wireless communication service, the frequency conversion relay apparatus currently uses a reference frequency which is a frequency of a signal received from a base station or an optical repeater. And a frequency converter configured to convert an idle frequency, which is not a frequency, wherein the received signal is transmitted through the converted idle frequency, reduced to the reference frequency, and transmitted to a mobile station. do.

According to another preferred embodiment of the present invention, in a frequency conversion relay apparatus of a time division wireless communication service, the frequency conversion relay apparatus is a frequency at which the base station does not currently use a reference frequency which is a frequency of a signal received from a mobile station. Including a frequency converter for converting the idle frequency, wherein the received signal is transmitted through the converted frequency, the frequency conversion relay apparatus is characterized in that the reduced to the reference frequency and transmitted to a base station or an optical repeater .

The frequency converter comprises: a PLL circuit for obtaining an oscillation output equal to the received reference frequency; And a converting unit converting the oscillation output frequency into an idle frequency.

The frequency converter may include an oven controlled crystal oscillator (OCXO) to maintain the received reference frequency.

The frequency conversion relay device includes a bandwidth pass filter for performing filtering on the received signal; And a low noise amplifier (LNA) for amplifying the signal filtered by the bandwidth pass filter.

The frequency conversion relay apparatus may further include a high power amplifier (HPA) for amplifying the signal with the converted idle frequency.

The frequency conversion relay apparatus may further include a synchronization controller for temporally synchronizing reception from the base station or optical repeater and transmission to or from the mobile station and transmission to the base station or optical repeater.

According to another preferred embodiment of the present invention, in a frequency conversion relay apparatus of a time division wireless communication service, a base frequency that is a frequency of a signal received from a base station or an optical repeater is a frequency not currently used by the base station. A downlink unit for converting to an idle frequency, receiving the signal transmitted through the converted idle frequency, reducing the signal to the reference frequency, and transmitting the signal to a mobile station; And converting a reference frequency, which is a frequency of a signal received from the mobile station, into an idle frequency, which is a frequency not currently used by the base station, receiving the signal transmitted through the converted idle frequency, and reducing the signal to the reference frequency. Provided is a frequency conversion relay apparatus comprising an uplink unit for transmitting to a repeater.

The frequency conversion relay apparatus may further include a switching unit, and the downlink unit and the uplink unit may be selectively operated by selective connection of the switching unit.

In addition, the frequency conversion relay device may be included in the base station or the optical repeater.

According to another aspect of the present invention, an optical relay device is provided.

According to a preferred embodiment of the present invention, in the optical relay apparatus for a wireless communication service, the optical relay apparatus receives a downlink signal received from the base station or another optical relay device from the base station or another optical relay device The base station converts a reference frequency, which is a frequency of the received signal, into an idle frequency, which is a frequency not currently used by the base station, and transmits it to a remote unit (RU), and converts an uplink signal converted to an idle frequency received from the RU. Provided is an optical relay apparatus, which reduces the reference frequency and transmits the signal to a base station or another optical repeater.

The wireless communication service may be at least one of a wireless broadband service (Wibro), a code division multiple access (CDMA), a wideband code division multiple access (WCDMA), and a global system for mobile telecommunication (GSM) scheme.

According to another aspect of the present invention, there is provided a recording medium recording a program for implementing the frequency conversion relay method.

According to one preferred embodiment of the present invention, a program of instructions that can be executed by the digital processing apparatus is tangibly implemented and can be read by the digital processing apparatus so that the frequency conversion relaying method of the time division wireless communication service is implemented. A recording medium for recording a program comprising: converting a reference frequency, which is a frequency of a signal received from a base station or an optical repeater, into a frequency not currently used by the base station; (B) transmitting the signal on the converted idle frequency; (C) reducing the frequency of the received signal to the reference frequency; And (d) transmitting the signal to the mobile station at the reduced reference frequency. There is provided a recording medium having recorded thereon a program for implementing a frequency conversion relay method.

According to another preferred embodiment of the present invention, a program of instructions executable by the digital processing apparatus is tangibly implemented and read by the digital processing apparatus such that the frequency conversion relaying method of the time division wireless communication service is implemented. In the recording medium on which a program can be recorded,

(A) converting a reference frequency, which is a frequency of a signal received from the mobile station, into an idle frequency, which is a frequency not currently used by the base station; (B) transmitting the signal at the converted frequency; (C) reducing the frequency of the received signal to the reference frequency; And (d) transmitting the signal to the base station at the reduced reference frequency. There is provided a recording medium having recorded thereon a program for implementing the frequency conversion relay method.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

In describing the drawings, similar reference numerals are used for similar elements. In the following description of the present invention, if it is determined that the detailed description of the related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component.

The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When a component is said to be "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but other components may be present in the middle. It should be understood.

On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention.

Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art.

Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art, and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, and the same or corresponding components will be denoted by the same reference numerals regardless of the reference numerals and redundant description thereof will be omitted.

First, a frequency conversion relay service system in which a frequency conversion relay method and apparatus according to the present invention can be used will be described with reference to FIG. 1.

1 is a diagram illustrating a frequency conversion relay service system in which a frequency conversion relay method and apparatus according to the present invention can be used.

As shown in FIG. 1, a frequency conversion relay service system in which a frequency conversion relay apparatus according to the present invention can be used has an area and coverage in which each radio frequency can reach, and in particular, mobile communication in such an area. In services, this is called a cell.

Meanwhile, the frequency conversion relay service system may include a cell transmitting a radio frequency (hereinafter referred to as a 'transmission cell') and a plurality of cells capable of receiving radio frequency from the transmitting cell (hereinafter referred to as a 'receive cell').

The transmitting cell includes a base station or an optical repeater 10 and a donor unit (DU) 11, and the base station or optical repeater 10 is connected to the DU 11 by wire or wirelessly. In the base station or the optical repeater 10, at least one of the base station and the optical repeater 10 may be selectively present in one cell.

Each receiving cell includes a remote unit (RU) 12a, 12b, 12c, 12d, 12e, and 12f for transmitting a radio frequency.

The DU 11 converts the downlink signal received by the base station or the optical repeater 10 into an idle frequency which is not currently used by the original service frequency F1, and transmits it to the RU, and the converted uplink received from the RU. The signal F2 is reduced to the original service frequency F1 and input to the base station or the optical repeater.

On the other hand, the RU 12 converts the downlink signal transmitted from the DU 11 to the original service signal and transmits the original signal to the mobile station, and transmits the signal received from the mobile station 13 to the idle frequency (F2). ) Is converted and transmitted to the DU 11.

On the other hand, the mobile station 13 is not limited as long as it is a device capable of wireless communication with the base station 10 or the RU 12. The mobile station 13 may be, for example, a notebook, a personal digital assistant (PDA), a personal multimedia player (PMP), or the like, as well as the most widely used portable terminal.

In this time division wireless communication method, the transmission of the signal received from the base station or the optical repeater 10 is referred to as downlink or downlink, and the reception of the signal to the base station or the optical repeater 10 up or up. This is called an uplink.

Meanwhile, in FIG. 1, for convenience of description, the cell is divided into a transmitting cell and a receiving cell, and each component is divided, but each cell performs both a radio frequency transmission and reception, and each cell has a base station or an optical repeater 10 ), DU 11 and RU 12. In addition, the DU 11 and the RU 12 may be implemented as separate devices, or may be implemented as a single device including both the DU 11 and the RU 12. It is apparent that both the DU 11 and the RU 12 may be included in the base station or the optical repeater 10 and implemented as a single device.

With reference to the configuration of the frequency conversion relay service system having such a configuration will be described the order in which the frequency conversion relay method according to the present invention is performed.

As described above, the frequency conversion relay transmits a signal from the base station or the optical repeater 10 to the base station or the optical repeater 10 and a downlink for transmitting a signal from the mobile station 13 to the base station or the optical repeater 10. Since there is an uplink, the order in which the frequency conversion relay method is performed will be divided into respective cases.

First, FIG. 2 is a flowchart illustrating a sequence performed by a downlink in a frequency conversion relay method according to an exemplary embodiment of the present invention.

As shown in Figure 2, in order to perform the downlink of the frequency conversion relay method according to the present invention, the DU 11 first receives a signal from the base station or optical repeater 10 (S200).

The reference frequency, which is the frequency of the signal received by the DU 11 from the base station or the optical repeater 10, is converted into a frequency not currently used by the base station or the optical repeater 10 (S202), and the signal of the converted frequency is amplified. (S204), the amplified signal is transmitted to the RU 12 (S206).

Meanwhile, the RU 12 reduces the signal received at the DU 11 to a reference frequency which is a frequency originally received from the signal of the base station or the optical repeater 10 at the DU 11 (S208), and converts the signal of the converted frequency. By amplifying (S210), the amplified signal is transmitted to the mobile station 13 (S212).

3 is a flowchart illustrating a sequence of performing uplink in the frequency conversion relay method according to an embodiment of the present invention.

As shown in FIG. 3, the RU 12 first receives a signal from the mobile station 13 to perform the uplink in the frequency conversion relay method according to the present invention (S300).

The reference frequency, which is the frequency of the signal received from the mobile station 13 to the RU 12, is converted into a frequency not currently used by the base station or the optical repeater 10 (S302), and the signal of the converted frequency is amplified (S204). In step S306, the amplified signal is transmitted to the DU 11.

Meanwhile, the DU 11 reduces the signal received at the RU 12 to a reference frequency, which is a frequency originally received from the mobile station 13 at the RU 12 (S308), and amplifies the signal at the converted frequency (S310). ), And transmits the amplified signal to the base station or optical repeater 10 (S312).

According to this frequency conversion relay method, the signal can be relayed using a frequency band not currently used by the base station or the optical repeater 10, and the final signal transmitted to the mobile station 13 is transmitted by the original reference frequency. Therefore, the existing base station or optical repeater 10 can be utilized as it is.

On the other hand, it is apparent to those skilled in the art that the frequency conversion relay method according to the present invention may be implemented and executed in the form of a program installed in the digital processing apparatus.

Referring to the frequency conversion relay method according to the present invention, a configuration of a donor unit (DU) 11 of the frequency conversion relay apparatus will be described first.

4 is a configuration diagram illustrating the configuration of the DU 11 of the frequency conversion relay apparatus according to an embodiment of the present invention.

As shown in FIG. 4, the DU 11 of the frequency conversion relay device according to the preferred embodiment of the present invention is a donor antenna 23, a band pass filter 24, 28, a coupler 25, and a synchronization unit. Control unit 26, RF (Radio Frequency) switch (27, 28, 36, 37), low noise amplifier (LNA) 29, down mixer 30, drive amplifiers (31, 33), Surface Acoustic Wave ) Filter 32, up mixer 34, high power amplifier (HPA) 35, RU opposing antenna 39, first local switch 40, first phase locked loop (PLL) circuit 41, Second Local Switch 42, Oven Controlled Crystal Oscillator (OCXO) 43, and Second PLL circuit 44 may be included.

The downlink in the DU 11, which may have such a configuration, first receives a base station or optical repeater 10 signal through a donor antenna 23 or an input port (not shown) of the DU 11 to pass a band. Passing through the filter 24 and the coupler 25 sequentially passes through the RF switch 27, 28 in the downlink path, and amplified to high power in the HPA 35 via the LNA 29 and the frequency converter 45 do.

It is then transmitted to the RU 12 via the RU opposing antenna 39 via the RF switches 36 and 37 and the band pass filter 38.

The uplink in the DU 11 passes through the band pass filter 38 via the RU opposing antenna 39 sequentially through the RF switches 37 and 28 in the uplink path, and the LNA 29. And amplifies the HPA 35 at high power through the frequency converter 45.

Then, the signal is transmitted to the base station or the optical repeater 10 through the donor antenna 23 through the RF switches 36 and 27 and the band pass filter 24.

On the other hand, synchronization of the downlink time and the time of the uplink is performed by controlling the RF switches 27, 28, 36, 37 to be synchronized at a specific time by the synchronization controller 26.

In the control of the RF switches 27, 28, 36, 37, the frequency converter 45 is used in both the downlink and the uplink.

During downlink time, the frequency of the original base station or optical repeater 10 (hereinafter referred to as 'F1') is input to the downmixer 30 via the first PLL circuit 41 and the first Local switch 40. Down-converts to an intermediate frequency (IF) (hereinafter referred to as 'IF') by supplying and up-mixing the signal from the second PLL circuit 44 via the second Local switch 42 By supplying to 34, the intermediate frequency IF is up-converted to a radio frequency (RF) and converted to a link frequency (F2) to be transmitted to the RU 12 at the time of upconverting.

In the uplink time, the input link frequency F2 is supplied to the down mixer 30 via the second PLL circuit 44 and the first Local switch 40 to downconvert to the intermediate frequency IF. By supplying the signal of the PLL 41 to the upmixer 34 via the second Local switch 42, the intermediate frequency IF is upconverted to the radio frequency, and up-converted to the original frequency F1 at the time of upconverting. Convert and transmit to the base station or optical repeater (10).

In this case, in order to maintain a reference frequency, which is a frequency transmitted and received from the base station or the optical repeater 10 or to the base station or the optical repeater 10 in consideration of the frequency stability, an oven controlled crystal oscillator (OCXO) 43 may be used.

With reference to the configuration of the DU 11 will be described with respect to the configuration of the RU 12 for receiving a radio frequency from the DU (11).

5 is a block diagram illustrating the configuration of the RU 12 of the frequency conversion relay apparatus according to an embodiment of the present invention.

As shown in FIG. 5, the RU 12 of the frequency conversion relay device according to the preferred embodiment of the present invention includes a link antenna 46, a band pass filter 47 and 61, a coupler 48, and a synchronization controller 50. ), RF switches (49, 51, 59, 60), LNA (52), down mixer (53), drive amplifiers (54, 56), SAW filter (55), up mixer (57), HPA (58), RU opposed antenna 62, first Local switch 63, first PLL circuit 64, second Local switch 65, OCXO 66, and second PLL circuit 67 may be included.

The downlink at the RU 12 receives the signal transmitted from the DU 11 to the link antenna 46 and passes through the band pass filter 47 and the coupler 48 to switch the RF switches 49 and 51 in the downlink path. ) Are sequentially passed through the LNA 52 and the frequency converter 68 and amplified by the HPA 58 at high power.

And it transmits to the mobile station 13 via the service antenna 62 through the RF switch 59, 60 and the band pass filter 61.

The uplink in the RU 12 passes through the band pass filter 61 through the service antenna 62 and sequentially passes through the RF switches 60 and 51 of the uplink path, and the LNA 52 and the frequency converter ( 68 to amplify the high power in the HPA (58).

And it is transmitted to the DU 11 through the link antenna 46 via the RF switch 59, 49 and the band pass filter 47.

In addition, the synchronization of the downlink time and the uplink time is performed by controlling the RF switches 27, 28, 36, 37 to be synchronized at a specific time by the synchronization controller 26.

On the other hand, in controlling the RF switches 27, 28, 36, 37, the frequency converter 45 is used in both the downlink and the uplink.

In the downlink time, down-converting to the intermediate frequency IF by supplying the input frequency F2 of the DU 11 to the downmixer 53 via the first PLL circuit 64 and the first Local switch 63. By supplying the signal of the second PLL circuit 67 to the upmixer 57 via the second Local switch 65, the intermediate frequency IF is upconverted to the radio frequency, and the mobile station 13 at the time of upconverting. To the original service frequency (F2) to be transmitted.

In the uplink time, down-converting to the intermediate frequency IF by supplying the input frequency F1 of the mobile station 13 to the downmixer 53 via the second PLL circuit 67 and the first Local switch 63. And converts the intermediate frequency IF to a radio frequency by supplying the signal of the first PLL circuit 64 to the upmixer 57 via the second Local switch 65, and transmitting it to the link when upconverting. Up-converts to the received frequency F2 and transmits the result to the DU 11.

In addition, in the case of the RU 12, an OBO 66 may be used to maintain the reference frequency in consideration of the frequency stability.

As described above, the DU 11 and the RU 12 may be included in one device, and may be included in a conventional base station or an optical repeater 10 to implement a frequency conversion relay method according to the present invention. Can be.

Hereinafter, when the functions of the DU 11 and the RU 12 are included in one device, the configuration thereof will be described with reference to FIG. 6.

6 is a block diagram illustrating a configuration of a frequency conversion relay apparatus according to an exemplary embodiment of the present invention.

As illustrated in FIG. 6, the frequency conversion relay apparatus according to the present invention may include a downlink unit 200 and an uplink unit 201.

First, the downlink unit 200 includes downlink IF input ports 157, RF switches 158, 165, 181 and 188, 2-Way dividers 159 and 182, drive amplifiers 160, 162, 167, 170, 183, 185, 190, 193, SAW filters 161,169, 184, 192, variable attenuators 163, 173, 186, 196, 2-Way combiners 164, 187, downlink IF output ports 166, downmixers 168, 191, bandpass filters 172 195), downlink first PLL circuit 174, downlink second PLL circuit 175, 10MHz reference frequency divider 176, 199, sync control 177, sync signal input port 178 and 10MHz reference It may include a frequency input port 179.

The uplink section 201 includes uplink IF input ports 180, RF switches 158, 165, 181, and 188, 2-Way dividers 159 and 182, drive amplifiers 160, 162, 167, 170, 183, 185, 190, and 193, SAW filters. (161,169, 184, 192), variable attenuators (163, 173, 186, 196), 2-Way combiners (164, 187), upmixers (168, 191), bandpass filters (172, 195), uplink first PLL (197) ), Uplink second PLL 198 and 10 MHz reference frequency dividers 176 and 199.

Referring to the signal processing of the downlink unit 200, first, the path of the downlink IF input port 157 received signal is opened at the RF switch 158 only at that time, and the signal is originally generated by the 2Way divider 158. The input signal F1 and the signal F2 to be frequency-converted are separated into paths.

The original signal F1 path is amplified to a proper level in the drive amplifier unit 160, and the SAW filter 161 filters and passes only a corresponding pass band to a proper level again in the drive amplifier unit 162. . Then, the variable attenuator 163 is combined with the signal F2 converted by the 2Way combiner 164 and output through the output side RF switch 165.

The signal F2 to be frequency converted is amplified to a suitable level in the drive amplifier unit 167, mixed in the downlink first PLL circuit 174 in the downmixer 168, converted into an intermediate frequency IF, and the SAW filter 169 ), Only the pass band is filtered and a time delay is given, and the drive amplifier unit 170 amplifies to an appropriate level again.

The upmixer 171 mixes with the second PLL circuit 175 to convert to the frequency (F2) to be converted, passes through the band pass filter 172 and passes through the variable attenuator 163 to the original signal at the 2Way combiner 164. In combination with (F1) and output through the output side RF switch (165).

That is, the original service frequency F1 is input from the downlink IF input port 157 and the original service signal F1 and the converted signal F2 are simultaneously output from the downlink IF output port 166.

In addition, SAW filters having the same time delay should be used to minimize the time delay difference when implementing the SAW filters 161 and 169 of each path.

Referring to the signal processing of the uplink unit 201, the original service signal F1 and the converted signal F2 received through the uplink IF input port 180 are routed only at the corresponding time at the RF switch 181. This signal is separated into the original input signal F1 and the frequency-converted signal F2 path in the 2Way divider 158.

The original signal F1 path is amplified to an appropriate level in the drive amplifier unit 183, and the SAW filter 184 filters and passes only the corresponding pass band, and amplifies to an appropriate level in the drive amplifier unit 185 again. .

Then, the signal F2 converted by the 2Way combiner 187 through the variable attenuator 186 is combined with the signal converted into the original service signal F1 and output through the output side RF switch 188.

The frequency-converted signal F2 is amplified to an appropriate level in the drive amplifier unit 190, mixed with the uplink first PLL circuit 197 in the downmixer 191, converted into an intermediate frequency IF, and the SAW filter 192. ), Only the pass band is filtered and a time delay is given, and the drive amplifier unit 193 amplifies the signal to an appropriate level.

The amplified signal is mixed in the second PLL circuit 198 in the upmixer 194, converted to the original service frequency F1, and passed through the variable attenuator 196 via the band pass filter 195 to the 2Way combiner 187. In combination with the original signal (F1) in the output via the RF switch 188.

That is, the original service signal F1 and the signal F2 converted into the link frequency are input from the uplink IF input port 180, and the original service signal F1 is output from the uplink IF output port 189. .

In addition, SAW filters having the same time delay should be used to minimize the time delay difference in implementing the SAW filters 184 and 192 of each path.

In the downlink unit 200 and the uplink unit 201, the timing synchronization and the frequency synchronization signal (for example, the synchronization synchronization and the frequency synchronization signal of the base station or the optical repeater 10 may be achieved with the base station or the optical repeater 10). , Reference 10MHz) can be received from the synchronization signal input port 178 and the 10MHz reference frequency input port 179 to be used.

Hereinafter, a case in which the frequency converter according to the present invention is implemented by being included in a conventional digital optical repeater will be described with reference to FIGS. 7 to 9. 7 to 9 illustrate a conventional digital optical repeater, the frequency converter according to the present invention is obvious that it can be implemented by being included in not only the digital optical repeater but also an analog optical repeater.

First, Figure 7 is a block diagram of a conventional digital optical repeater that can be included in the frequency conversion repeater according to the present invention.

7 is a block diagram of a conventional time division type digital optical repeater in which MIMO (Multi Input Multi Output) is implemented.

As shown in FIG. 7, the conventional digital optical repeater may include a main hub unit 95 and a remote unit 96.

The operation of the digital optical repeater will be described with reference to FIG. 7. First, in downlink, the main hub unit 95 converts the IF signal of the base station from the downlink main path IF signal input port 69 to the downlink diversity path IF signal. The signal is received by the input port 70 and amplified by the signal downlink drive amplifier unit 75 to an appropriate level.

The digital signal and the optical signal are converted by the AD / DA conversion and the digital optical transmission / reception unit 77 and transmitted to the remote unit 96 via the optical line 78. The remote unit 96 converts the digital optical signal transmitted from the main hub unit 95 to the analog IF signal by the AD / DA conversion and the digital optical transmission / reception unit 81 via the optical switch 80, and downlink upconverting. The units 82 and 89 convert to radio frequencies, respectively.

The signal converted to radio frequency is amplified to a high output at each HPA 83, 91 and passed through a band pass filter 85, 93 via an RF switch 85, 93 to each mobile station facing antenna 86, 94. Output through

On the other hand, in the uplink, signals received through respective mobile station facing antennas 86 and 94 pass through RF bands 85 and 93 and LNAs 88 and 90 through respective band pass filters 85 and 93. Then, the downlink converting unit 87 is down-converted, respectively.

The downconverted intermediate frequency IF is converted into a digital signal and an optical signal by the AD / DA conversion and the digital optical transmission / reception unit 81 and transmitted to the main hub unit 96 through the optical line 78.

The main hub unit 96 converts the digital optical signal transmitted from the remote unit 96 into an analog IF signal by the AD / DA conversion and the digital optical transmission / reception unit 77, and the appropriate level in the uplink drive amplifier unit 76. After the amplification, each of the uplink Main Path IF signal output port 71 and the uplink Diversity Path IF signal output port 72 are outputted and connected to the base station 10.

Meanwhile, as described above, the base station 10 receives a synchronization signal and a reference frequency signal for time and frequency synchronization with the base station and connects the base station with the base station.

With reference to the configuration of the conventional digital optical repeater will be described with reference to Figs. 8 and 9 for an example of implementing the conventional optical repeater including the frequency conversion repeater according to the present invention.

First, FIG. 8 is a diagram illustrating a configuration of a frequency conversion relay device (DU) of a frequency conversion relay apparatus by combining a frequency converter according to the present invention to a main hub (MHU) of a conventional digital optical repeater.

FIG. 8 includes the downlink part performing the downlink and the uplink part performing the uplink of the frequency conversion relay apparatus according to the present invention as described above in the main hub unit 125 included in the conventional optical repeater of FIG. The configuration is shown when the optical repeater already in service serves as the DU 11 of the frequency conversion relay system.

The output of the already-operated optical repeater outputs only the service signal 1FA and simultaneously outputs the service signal 1FA and the converted signal 2FA by adding the downlink unit and the uplink unit.

In addition, the downlink unit and the uplink unit including the switching unit may be coupled to the conventional optical repeater by selectively operating the downlink unit and the uplink unit by selective connection of the switching unit.

On the other hand, the RU 12 converts the converted signal 2FA back to the original service signal 1FA and outputs the frequency.

Therefore, it is possible to secure coverage by installing only the RU 12 without additionally installing the equipment of the DU 11, and since the optical repeater that is already in operation can be utilized as the DU 11, a cost reduction effect can be obtained.

FIG. 9 illustrates the downlink unit performing the downlink and the uplink unit performing the uplink. The AD / DA conversion and digital optical transceiver 77 of the remote unit 156 included in the conventional optical repeater described in FIG. When connected to the stage is shown the configuration.

Even in this case, the service signal 1FA and the converted signal 2FA are simultaneously output by adding the downlink part and the uplink part to the optical repeater already in operation, and the RUs 8 and 19 output the converted signal 2FA. By converting the signal back into the original service signal 1FA and outputting it, frequency conversion and relaying can be performed.

Therefore, as shown in FIG. 8, the RU 11 can be installed to secure coverage by installing only the RUs 8 and 19 without additionally installing the equipment of the DU 11. This can result in cost savings.

On the other hand, such a conventional optical repeater does not necessarily need to be a time-division optical repeater, but there is no limitation as long as it can use the idle frequency of the current base station or optical repeater.

Accordingly, various types of communication services may be provided by adding a frequency conversion relay apparatus according to the present invention to a base station or an optical repeater which is pre-installed for providing various conventional communication services, for example, a mobile communication service.

Preferred embodiments of the present invention described above are disclosed for purposes of illustration, and those skilled in the art will be able to make various modifications, changes, and additions within the spirit and scope of the present invention. Additions should be considered to be within the scope of the following claims.

As described above, according to the frequency conversion relay method and apparatus according to the present invention, even in a time-division wireless communication service such as Wibro service, the wireless communication service may be increased not only in the downtown but also in a low traffic area such as a suburban area. There is an advantage that can be expanded.

In addition, the present invention has the advantage of reducing the operation and installation costs of the wireless communication service while expanding the coverage of the wireless communication service in a time division wireless communication service such as Wibro service.

Claims (20)

In the frequency conversion relay method of a time division wireless communication service, (A) converting a reference frequency, which is a frequency of a signal received from a base station or an optical repeater, into an idle frequency, which is a frequency not currently used by the base station; (B) transmitting the signal on the converted idle frequency; (C) reducing the frequency of the received signal to the reference frequency; And And transmitting (d) the signal to a mobile station at the reduced reference frequency. In the frequency conversion relay method of a time division wireless communication service, (A) converting a reference frequency, which is a frequency of a signal received from the mobile station, into an idle frequency, which is a frequency not currently used by the base station; (B) transmitting the signal on the converted idle frequency; (C) reducing the frequency of the received signal to the reference frequency; And And transmitting (d) the signal to the base station or the optical repeater at the reduced reference frequency. The method according to claim 1 or 2, Step (a) is, And performing filtering and amplification on the received signal. The method according to claim 1 or 2, Step (b) is, And amplifying the signal with the converted idle frequency. The method according to claim 1 or 2, Step (c) is, And performing filtering and amplification on the received signal. The method according to claim 1 or 2, Step (d) is, Frequency conversion relay method characterized in that it is performed in synchronization with the time step (a) is performed. A frequency conversion relay apparatus for a time division wireless communication service, The frequency conversion relay apparatus includes a frequency converter for converting a reference frequency, which is a frequency of a signal received from a base station or an optical repeater, into an idle frequency that is not currently used by the base station, And the received signal is transmitted through the converted idle frequency, reduced to the reference frequency, and transmitted to a mobile station. A frequency conversion relay apparatus for a time division wireless communication service, The frequency conversion relay apparatus includes a frequency converter for converting a reference frequency which is a frequency of a signal received from a mobile station into an idle frequency which is a frequency not currently used by a base station, And the received signal is transmitted through the converted idle frequency, reduced to the reference frequency, and transmitted to a base station or an optical repeater. The method according to claim 7 or 8, The frequency converter, A PLL circuit for obtaining an oscillation output equal to the received reference frequency; And And a converting unit converting the oscillated output reference frequency into an idle frequency. The method according to claim 7 or 8, The frequency converter, And an oven controlled crystal oscillator (OCXO) to maintain the received reference frequency. The method according to claim 7 or 8, The frequency conversion relay device, A bandwidth pass filter for performing filtering on the received signal; And And a low noise amplifier (LNA) for amplifying the signal filtered by the bandwidth pass filter. The method according to claim 7 or 8, The frequency conversion relay device, And a high power amplifier (HPA) for amplifying the signal with the converted idle frequency. The method according to claim 7 or 8, The frequency conversion relay device, And a synchronization controller for temporally synchronizing the reception from the base station or the optical repeater to the mobile station or the reception from the mobile station and the transmission to the base station or the optical repeater. A frequency conversion relay apparatus for a time division wireless communication service, Converting a reference frequency, which is a frequency of a signal received from a base station or an optical repeater, into an idle frequency that is not currently used by the base station, receiving the signal transmitted through the converted idle frequency, and reducing the frequency to the reference frequency; A downlink unit for transmitting to the same station; And The base station or the optical repeater converts the reference frequency, which is the frequency of the signal received from the mobile station, into an idle frequency that is not currently used by the base station, receives the signal transmitted through the converted idle frequency, and reduces the signal to the reference frequency. Frequency conversion relay apparatus comprising an uplink for transmitting to. The method of claim 14, The frequency conversion relay device further includes a switching unit, And the downlink unit and the uplink unit are selectively operated by selective connection of the switching unit. The method according to any one of claims 7, 8 and 14, And the frequency conversion relay device is included in the base station or the optical repeater. In the optical relay device for a wireless communication service, The optical relay device idles a downlink signal received by a base station or another optical relay device, a reference frequency which is a frequency of a signal received from the base station or another optical relay device, which is a frequency not currently used by the base station. And converts the frequency into a remote unit (RU), reduces the uplink signal converted into an idle frequency received from the RU to a reference frequency, and transmits the signal to a base station or another optical repeater. The method of claim 17, The wireless communication service, An optical relay apparatus comprising at least one of a wireless service such as WiBro (Wibro), Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA), and Global System For Mobile Telecommunication (GSM) scheme. A recording medium on which a program of instructions that can be executed by a digital processing apparatus is tangibly implemented so as to implement a frequency conversion relay method of a time division wireless communication service, and which records a program that can be read by the digital processing apparatus. (A) converting a reference frequency, which is a frequency of a signal received from a base station or an optical repeater, into an idle frequency, which is a frequency not currently used by the base station; (B) transmitting the signal on the converted idle frequency; (C) reducing the frequency of the received signal to the reference frequency; And And (d) transmitting the signal to the mobile station at the reduced reference frequency. A recording medium on which a program of instructions that can be executed by a digital processing apparatus is tangibly implemented so as to implement a frequency conversion relay method of a time division wireless communication service, and which records a program that can be read by the digital processing apparatus. (A) converting a reference frequency, which is a frequency of a signal received from the mobile station, into an idle frequency, which is a frequency not currently used by the base station; (B) transmitting the signal on the converted idle frequency; (C) reducing the frequency of the received signal to the reference frequency; And And (d) transmitting the signal to a base station or an optical repeater at the reduced reference frequency.

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