KR20090051983A - Apparatus for converting signal for wireless communication system - Google Patents

Abstract

A signal conversion device for a wireless communication system is disclosed. The first switch is switched between a first fixed side contact to which the first signal received from the mobile station is input and a second fixed side contact to which the second signal to be transmitted to the mobile station is input. The first bandpass filter selectively filters frequencies of a predetermined band from the first signal and the second signal. The first amplifier amplifies and outputs the signal passing through the first bandpass filter. The gain adjuster adjusts the gain of the signal amplified by the first amplifier. The second switch is electrically connected to a first fixed side contact electrically connected to a demodulator for demodulating the signal output from the gain regulator to a switching station or base station, and a transmit / receive antenna for transmitting the signal output from the gain regulator to the mobile station. It is switched between the second fixed side contact. According to the present invention, the performance, size and efficiency of the system can be improved by sharing the transmission and reception paths of the RF band and the IF band in a time division mobile communication system.

Base station system, relay system, uplink, downlink, signal conversion,

Description

Apparatus for converting signal for wireless communication system

The present invention relates to a signal conversion device for a wireless communication system, and more particularly, to a signal conversion device for the common use of the transmission and reception path of the time division multiplexing mobile communication system.

The mobile communication system is largely composed of an exchange station system, a base station system, and a relay station system. Among them, the base station system is a component located at the last stage of transmitting and receiving signals to and from the wireless terminal of the subscriber. 1 illustrates a configuration of a base station apparatus of a conventional time division duplex (TDD) mobile communication system.

Referring to FIG. 1, a base station apparatus 100 of a TDD mobile communication system includes a transceiver antenna 110, a signal branch unit 120, an RF signal processor 140, an IF signal processor 160, and a signal converter 190. It is composed.

The transmit / receive antenna 110 receives an RF signal from a mobile terminal or transmits an RF signal to the mobile terminal. The signal branch unit 120 branches the signal received from the mobile terminal through the transmit / receive antenna 110 to the switching station to the uplink or transmits the signal received from the switching station through the transmit / receive antenna 110 to the mobile terminal. Branch to downlink to forward to. To this end, the signal branch unit 120 includes a cavity bandpass filter 122, a brancher 124, a first single single throw (SPST) switch 126, a second SPST switch 128, and an amplifier 130. It is provided.

The cavity bandpass filter 122 filters and outputs only signals of a specific frequency band from an input signal by using a principle in which resonant frequencies vary according to the size of a cavity formed in an empty space surrounded by metal. The diverter 124 varies the output direction according to the input direction of the signal. If the signal is input from the cavity bandpass filter 122, the tap-off 124 outputs an input signal to the first SPST switch 126, and if the signal is input from the second SPST switch 128, the tap-off 124 is input. The signal is output to the cavity bandpass filter 122. The first and second SPST switches 126 and 128 each have a fixed side contact point and a movable side contact point to selectively perform line connection and interruption operations by 'On' and 'Off' operations. The amplifier 130 amplifies the signal input from the RF signal processor 140 and outputs the signal to the second SPST switch 128. Since the signal amplified from the amplifier 130 is transmitted to the mobile terminal through the transmission and reception antenna 110, the amplifier 130 employs a high output amplifier.

The RF signal processor 140 processes an RF signal received from the mobile terminal and an RF signal to be transmitted to the mobile terminal. To this end, the RF signal processor 140 may include a first amplifier 142, a first gain adjuster 144, a second amplifier 146, a first dielectric bandpass filter 148, and a second dielectric bandpass filter 150. And a third amplifier 152 and a second gain adjuster 154.

The first amplifier 142 amplifies the RF signal received from the mobile terminal. At this time, in order to maintain the quality of the signal, the first amplifier 142 employs a low noise amplifier. The first gain adjuster 144 adjusts the gain of the signal input from the first amplifier 142. The second amplifier 146 amplifies again to increase the gain of the signal input from the first gain adjuster 144. The first dielectric bandpass filter 148 selectively filters and outputs only a predetermined range of frequencies from the signal input from the second amplifier 146. In addition, the second dielectric bandpass filter 150 selectively filters and outputs only a predetermined range of frequencies from the signal input from the IF signal processor 160. A filter fabricated using a dielectric resonator shows high frequency selectivity. The third amplifier 152 amplifies to increase the gain of the signal input from the second dielectric bandpass filter 150, and the second gain adjuster 154 adjusts the gain of the signal input from the third amplifier 152. do.

Among the components of the RF signal processor 140 as described above, the first amplifier 142, the first gain adjuster 144, the second amplifier 146, and the first dielectric bandpass filter 148 may use an uplink. The second dielectric bandpass filter 150, the third amplifier 152, and the second gain regulator 154 form a downlink.

The IF signal processor 160 converts the IF signal input from the signal converter 190 into an RF signal, and converts the RF signal input from the RF signal processor 140 into an IF signal. To this end, the IF signal processor 160 includes a first multiplier 162, a first local oscillator 164, a first surface acoustic wave band pass filter 166, a first amplifier 168, a first SPST switch 170, a first 2SPST switch 172, a second amplifier 174, a second surface acoustic wave bandpass filter 176, a second multiplier 178 and a second local oscillator 180.

The first multiplier 162 multiplies the reference frequency signal input from the first local oscillator 164 by the signal input from the first dielectric bandpass filter 148 of the RF signal processor 140 and outputs the multiplied signal. The first surface acoustic wave SAW bandpass filter 166 selectively filters and outputs only a predetermined range of frequencies from a signal input from the first multiplier 162. The first amplifier 168 amplifies to increase the gain of the signal input from the first surface acoustic wave bandpass filter 166. The first SPST switch 170 has one fixed side contact point and one movable side contact point, and is selectively inputted from the first amplifier 168 by selectively performing connection and interruption of the line by 'On' and 'Off' operation. The signal is selectively output to the signal converter 190. The second SPST switch 172 selectively outputs a signal input from the signal converter 190 to the second amplifier 174 by selectively performing connection and interruption of the line by 'On' and 'Off' operations. . The second amplifier 174 amplifies to increase the gain of the signal input from the second SPST switch 172. The second surface acoustic wave bandpass filter 176 selectively filters and outputs only a predetermined range of frequencies from the signal input from the second amplifier 174. The second multiplier 178 multiplies the signal input from the second surface acoustic wave bandpass filter 176 and the reference frequency signal input from the second local oscillator 180 to multiply the second dielectric bandpass filter of the RF signal processor 140. Output to 150.

Among the components of the IF signal processor 160 as described above, the first multiplier 162, the first local oscillator 164, the first surface acoustic wave band pass filter 166, the first amplifier 168, and the first SPST. The switch 170 constitutes an uplink and includes a second SPST switch 172, a second amplifier 174, a second surface acoustic wave bandpass filter 176, a second multiplier 178, and a second local oscillator 180. ) Constitutes a downlink.

The signal converter 190 selectively performs modulation or demodulation, and analog to digital conversion or digital to analog conversion according to the input direction of the signal. The signal converter 190 includes a D / A converter 192, a modulator 194, a demodulator 196, and an A / D converter 198. The D / A converter 192 converts the digital signal transmitted from the switching center, relay station or other base station into an analog signal. The modulator 194 modulates an analog signal input from the D / A converter 192 and outputs the modulated analog signal to the second SPST switch 172 of the IF signal processor 160. The demodulator 196 demodulates and outputs a signal input from the first SPST switch 170 of the IF signal processor 160, and the A / D converter 198 converts an analog signal input from the demodulator 196 into a digital signal. To print.

Among the components of the signal converter 190 described above, the D / A converter 192 and the modulator 194 constitute a downlink, and the demodulator 196 and the A / D converter 198 perform uplink. Configure.

In the conventional TDD mobile communication system operating as described above, power is supplied to the downlink section in the uplink section, and power is supplied to the uplink section in the downlink section, resulting in inefficient power distribution. In addition, since two paths, an uplink and a downlink, must be configured, there is a problem that a large amount of space is occupied.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a signal conversion device for a wireless communication system capable of efficient power management and size reduction of a device.

In order to achieve the above technical problem, a preferred embodiment of a signal conversion apparatus for a wireless communication system according to the present invention includes a first fixed side contact to which a first signal received from a mobile station is input and a second signal to be transmitted to the mobile station. A first switch switched between input second fixed side contacts; A first bandpass filter for selectively filtering a frequency of a predetermined band from the first signal and the second signal; A first amplifier for amplifying and outputting a signal passing through the first band pass filter; A gain adjuster for adjusting the gain of the signal amplified by the first amplifier; And a first fixed side contact electrically connected to a demodulator for demodulating the signal output from the gain regulator to a switching station or a base station, and a second antenna electrically connected to a transmission / reception antenna for transmitting a signal output from the gain regulator to a mobile station. And a second switch switched between the two fixed side contacts.

According to the signal conversion device for a wireless communication system according to the present invention, by using the uplink signal converter and the downlink signal converter in common, it is possible to use the power efficiently, and the spatial specific gravity is smaller than the conventional method. It can be configured. In addition, since the signal converter can be used in common, the number of devices having the same characteristics can be reduced by half, thereby reducing the cost by about half. Furthermore, when the signal conversion device for a wireless communication system according to the present invention is applied to a multiple input multiple output (MIMO) scheme used in a TDD mobile communication system, a single local oscillator transmits each MIMO path. Receiving paths can be shared so that the number of paths can be reduced by half compared to the Diversity method or the MIMO method using the conventional signal conversion device.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of a signal conversion apparatus for a wireless communication system according to the present invention.

2 is a diagram showing the configuration of a first preferred embodiment of a signal conversion apparatus for a wireless communication system according to the present invention.

2, the signal conversion apparatus 200 for a wireless communication system according to the present invention includes a transmission / reception antenna 210, a signal branch unit 220, an RF signal processing unit 240, and a signal conversion unit 290. . In the configuration shown in FIG. 2, the RF signal processor 240 is a component commonly used for uplink and downlink. In this case, the configuration and operation of the transmission / reception antenna 210, the signal branch unit 220, and the signal conversion unit 290 are the same as those of the corresponding components of the conventional signal conversion apparatus 100 described with reference to FIG. 1. Therefore, detailed description thereof will be omitted.

The RF signal processor 240 may include a first amplifier 242, a first single pole double throw (SPDT) switch 244, a dielectric bandpass filter 246, a second amplifier 248, a gain adjuster 250, and a second SPDT. And a switch 252.

The first amplifier 242 amplifies the RF signal received from the mobile terminal as a low noise amplifier. The first single pole double throw (SPDT) switch 244 is switched between two fixed side contacts and selectively transmits a signal input through each fixed side contact by a switching operation of the movable side contact to the dielectric band pass filter 246. Will output In this case, the first fixed side contact is electrically connected to the low noise amplifier 242, and the RF signal received from the mobile terminal amplified by the low noise amplifier 242 is input to the first fixed side contact. The second fixed side contact is also electrically connected to the modulator 294 of the signal converter 290, and an RF signal to be transmitted to the mobile station is input to the second fixed side contact. The dielectric bandpass filter 246 selectively filters and outputs only a predetermined range of frequencies from the signal input from the first SPDT switch 244. The second amplifier 248 amplifies to increase the gain of the signal passing through the dielectric bandpass filter 246, and the gain adjuster 250 adjusts the gain of the signal input from the second amplifier 248. The second SPDT switch 252 is switched between the two fixed side contacts and inputs a signal input through the movable side contact by the switching operation of the movable side contact to the demodulator 296 and the signal branch 220 of the signal converter 290. The amplifier 230 selectively outputs the amplifier 230.

As described above, the first embodiment of the present invention described with reference to FIG. 2 realizes minimization of a circuit through direct conversion of an RF signal, and is provided at the front and rear ends according to the signal transmission direction of the RF signal processor 240. By controlling the switching operation of the provided SPDT switch, a signal transmitted through the uplink and the downlink by the same device may be commonly processed. To this end, when a signal received from the mobile station and passed through the first amplifier 242 is input to the dielectric bandpass filter 246 by the switching operation of the first SPDT switch 244, the second SPDT switch 252 is the gain regulator 250. It is switched to provide a signal input from the modulator 296 of the signal converter 290. In addition, when the signal to be transmitted to the mobile station through the modulator of the signal converter 290 is input to the dielectric bandpass filter 246 by the switching operation of the first SPDT switch 244, the second SPDT switch 252 is a gain adjuster 250 In order to provide a signal input from the transmitting and receiving antenna to the high output amplifier 230 of the signal branch (210).

3 is a diagram showing the configuration of a second preferred embodiment of a signal conversion apparatus for a wireless communication system according to the present invention.

Referring to FIG. 3, the signal conversion apparatus 300 for a wireless communication system according to the present invention includes a transceiver antenna 310, a signal branch unit 320, an RF signal processor 340, an IF signal processor 360, and a signal converter. The unit 390 is provided. In the configuration shown in FIG. 3, the RF signal processor 340 and the IF signal processor 360 are components commonly used for uplink and downlink. In this case, the configuration and operation of the transmission / reception antenna 310, the signal branching unit 320, and the signal conversion unit 390 are the same as those of the corresponding components of the conventional signal conversion apparatus 100 described with reference to FIG. 1. Therefore, detailed description thereof will be omitted.

The RF signal processor 340 may include a first amplifier 342, a first single double throw (SPDT) switch 344, a dielectric bandpass filter 346, a second amplifier 348, a gain adjuster 350, and a second SPDT. And a switch 352.

The first amplifier 342 amplifies the RF signal received from the mobile terminal as a low noise amplifier. The first SPDT switch 344 is switched between the two fixed side contacts and selectively outputs a signal input through each fixed side contact to the dielectric band pass filter 346 by the switching operation of the movable side contacts. At this time, the first fixed side contact of the first SPDT switch 344 is electrically connected to the low noise amplifier 342, and the RF signal received from the mobile terminal amplified by the low noise amplifier 342 is input to the first fixed side contact. . In addition, the second fixed side contact is electrically connected to the first multiplier 370 of the IF signal processor 360, and the RF signal to be transmitted to the mobile station is input to the second fixed side contact. The dielectric bandpass filter 346 selectively filters and outputs only a predetermined range of frequencies from the signal input from the first SPDT switch 344. The second amplifier 348 amplifies to increase the gain of the signal passing through the dielectric bandpass filter 346, and the gain adjuster 350 adjusts the gain of the signal input from the second amplifier 348. The second SPDT switch 352 switches between the two fixed side contacts and divides the signal inputted through the movable side contact by the switching operation of the movable side contact with the second multiplier 372 of the IF signal processor 360. It is selectively output to the amplifier 330 of the base 320.

The IF signal processor 360 converts an IF signal input from the signal converter 390 into an RF signal, and converts an RF signal input from the RF signal processor 340 into an IF signal. To this end, the IF signal processor 360 may include a first SPDT switch 362, an amplifier 364, a surface acoustic wave bandpass filter 366, a second SPDT switch 368, a first multiplier 370, and a second multiplier 372. A local oscillator 374 and a power divider 376.

The first SPDT switch 362 is switched between two fixed side contacts and selectively outputs a signal input through each fixed side contact to the amplifier 364 by a switching operation of the movable side contact. In this case, the first fixed side contact of the first SPDT switch 362 is electrically connected to the second multiplier 372, and the second fixed side contact is electrically connected to the modulator 394 of the signal converter 390. The amplifier 364 amplifies to increase the gain of the signal input from the first SPDT switch 362, and the surface acoustic wave bandpass filter 366 selectively filters only a predetermined range of frequencies from the signal input from the amplifier 364. Output The second SPDT switch 368 is switched between the two fixed side contacts and receives a signal from the surface acoustic wave bandpass filter 366 and the first multiplier 370 through the movable side contacts by a switching operation of the movable side contacts. The demodulator 396 of the converter 390 is selectively output. The first multiplier 370 multiplies the signal input from the second SPDT switch 368 with the reference frequency signal input from the power divider 376 and outputs the multiplied signal to the first SPDT switch 344 of the RF signal processor 340. At this time, the output terminal of the first multiplier 370 and the first fixed side contact of the first SPDT switch 344 of the RF signal processor 340 are electrically connected to each other. In addition, the second multiplier 372 multiplies the signal output from the first fixed side contact point of the second SPDT switch 352 of the RF signal processing unit 340 by the reference frequency signal input from the power divider 376 and thus the first SPDT switch 362. Output to the 1st fixed side contact of). Local oscillator 374 provides a reference frequency signal having a predetermined frequency to power divider 376.

As described above, the second embodiment of the present invention described with reference to FIG. 3 includes a front end of each of the signal processing units 340 and 360 according to a signal transmission direction of the RF signal processing unit 340 and the IF signal processing unit 360. By controlling the switching operation of the SPDT switch provided at the rear end, a signal transmitted through the uplink and the downlink by the same device can be commonly processed. To this end, when a signal received from the mobile station and passed through the first amplifier 342 to the dielectric bandpass filter 346 by the switching operation of the first SPDT switch 344 of the RF signal processor 340 is input, the second SPDT switch 352. ) Is switched to provide a signal input from the gain adjuster 350 to the modulator 396 of the signal converter 390. In this case, the first SPDT switch 362 of the IF signal processor 360 is switched so that the signal input from the second multiplier 372 is output to the amplifier 364, and the second SPDT switch 368 of the IF signal processor 360 is The signal input from the surface acoustic wave bandpass filter 366 is switched to be output to the demodulator 396 of the signal converter 390.

4 is a diagram showing the configuration of a third preferred embodiment of a signal conversion apparatus for a wireless communication system according to the present invention.

Referring to FIG. 4, the signal conversion apparatus 400 for a wireless communication system according to the present invention includes a transceiver antenna 410, a signal branch unit 420, an RF signal processor 440, an IF signal processor 460, and a signal converter. The unit 490 is provided. In the configuration shown in FIG. 4, the RF signal processor 440 and the IF signal processor 460 are components commonly used for uplink and downlink. In this case, the configuration and operation of the transmission / reception antenna 410, the signal branching unit 420, and the signal conversion unit 490 are the same as those of the corresponding components of the conventional signal conversion apparatus 100 described with reference to FIG. 1. Therefore, detailed description thereof will be omitted.

The RF signal processor 440 may include a first amplifier 442, a first single double throw (SPDT) switch 444, a dielectric bandpass filter 446, a second amplifier 448, a gain adjuster 450, and a second SPDT. And a switch 452.

The first amplifier 442 amplifies the RF signal received from the mobile terminal as a low noise amplifier. The first SPDT switch 444 is switched between the two fixed side contacts and selectively outputs a signal input through each fixed side contact to the dielectric band pass filter 446 by the switching operation of the movable side contacts. In this case, the first fixed side contact of the first SPDT switch 444 is electrically connected to the low noise amplifier 442, and the RF signal received from the mobile terminal amplified by the low noise amplifier 442 is input to the first fixed side contact. . In addition, the second fixed side contact is electrically connected to the second fixed side contact of the fourth SPDT switch 476 of the IF signal processor 460. The dielectric bandpass filter 446 selectively filters and outputs only a predetermined range of frequencies from the signal input from the first SPDT switch 444. The second amplifier 448 amplifies to increase the gain of the signal passing through the dielectric bandpass filter 446, and the gain adjuster 450 adjusts the gain of the signal input from the second amplifier 448. The second SPDT switch 452 is switched between the two fixed side contacts and the first fixed of the third SPDT switch 470 of the IF signal processing unit 460 for the signal input through the movable side contact by the switching operation of the movable side contact. It outputs selectively to the station and the amplifier 430 of the signal branch 420.

The IF signal processor 460 converts an IF signal input from the signal converter 490 into an RF signal, and converts an RF signal input from the RF signal processor 440 into an IF signal. To this end, the IF signal processor 460 may include a first SPDT switch 462, an amplifier 464, a surface acoustic wave bandpass filter 466, a second SPDT switch 468, a third SPDT switch 470, a multiplier 472, and a local part. An oscillator 474 and a fourth SPDT switch 476 are provided.

The first SPDT switch 462 is switched between two fixed side contacts and selectively outputs a signal input through each fixed side contact to the amplifier 464 by a switching operation of the movable side contact. In this case, the first fixed side contact of the first SPDT switch 462 is electrically connected to the first fixed side contact of the fourth SPDT switch 476, and the second fixed side contact is connected to the modulator 494 of the signal converter 490. Electrically connected. The amplifier 464 amplifies to increase the gain of the signal input from the first SPDT switch 462, and the surface acoustic wave bandpass filter 466 selectively filters only a predetermined range of frequencies from the signal input from the amplifier 464. Output The second SPDT switch 468 is switched between the two fixed side contacts and receives a signal input from the surface acoustic wave bandpass filter 466 through the movable side contact by the switching operation of the movable side contact. It outputs selectively to the 2 fixed side contacts and the demodulator 496 of the signal converter 490.

The third SPDT switch 470 is switched between the two fixed side contacts and selectively outputs a signal input through each fixed side contact to the multiplier 472 by the switching operation of the movable side contacts. In this case, the first fixed side contact of the third SPDT switch 470 is electrically connected to the first fixed side contact of the second SPDT switch 452 of the RF signal processor 440, and the second fixed side contact is the second SPDT switch 468. Is electrically connected to the second fixed side contact. The multiplier 470 multiplies the signal input from the third SPDT switch 470 with the reference frequency signal input from the local oscillator 474 and outputs the multiplied signal to the fourth SPDT switch 476. The fourth SPDT switch 476 is switched between the two fixed side contacts and the signal input through the movable side contact by the switching operation of the movable side contact to the first fixed side contact and the RF signal processor of the first SPDT switch 462. And selectively output to the second fixed side contact of the first SPDT switch 444 of 440.

As described above, the third embodiment of the present invention described with reference to FIG. 4 is provided in each of the signal processing units 440 and 460 according to the signal transmission directions of the RF signal processing unit 440 and the IF signal processing unit 460. By controlling the switching operation of the SPDT switch, a signal transmitted through the uplink and the downlink by the same device can be commonly processed. In particular, since one multiplier 472 and one local oscillator 474 are commonly used for the uplink and the downlink, the separation between the uplink and the downlink can be increased, thereby improving the stabilization of signals between the transmission and reception. . To this end, when a signal received from the mobile station through the first amplifier 442 through the dielectric bandpass filter 446 by the switching operation of the first SPDT switch 444 of the RF signal processor 440 is input, the second SPDT switch 452 is input. ) Is switched to provide a signal input from the gain adjuster 450 to the third SPDT switch 470 of the IF signal processor 460. At this time, the third SPDT switch 470 of the IF signal processing unit 460 is switched so that the signal input through the second SPDT switch 452 of the RF signal processing unit 440 is output to the multiplier 472, and the IF signal processing unit 460 The fourth SPDT switch 476 is switched to output the signal input from the multiplier 472 to the first SPDT switch 462 of the IF signal processor 460. In addition, the first SPDT switch 462 of the IF signal processing unit 460 is switched so that the signal input through the fourth SPDT switch 476 of the IF signal processing unit 460 is output to the amplifier 464, and the IF signal processing unit 460 The second SPDT switch 462 is switched so that the signal input from the amplifier 464 is output to the demodulator 496 of the signal converter 490.

Meanwhile, FIGS. 5 to 7 illustrate a state in which embodiments of the present invention described with reference to FIGS. 2 to 4 are applied to a TDD mobile communication digital relay system using a MIMO scheme. The MIMO scheme illustrated in FIG. 5 is an example of implementing a TDD mobile communication digital relay system by employing the first embodiment of the present invention illustrated in FIG. 2 in parallel. In addition, the MIMO scheme shown in FIGS. 6 and 7 is a MIMO scheme having two receiving stages and two transmitting stages (2 Tx, 2 Rx: 2T2R), respectively. It is an example of implementing a TDD mobile communication digital relay system by employing three embodiments in parallel. In this case, one local oscillator (620, 720) may be commonly used for a plurality of channels, and reference frequencies may be applied to each multiplier using an appropriate number of power dividers 630, 640, 650, and 730 according to the number of multipliers. Provide a signal. 5 to 7 illustrate the TDD mobile communication digital relay system of the 2R MIMO scheme to which the embodiments of the present invention are applied, the number of channels may be increased.

Since the signal conversion device for a wireless communication system according to the present invention uses the uplink signal converter and the downlink signal converter in common, the timing accuracy of the transmission / reception signal between the uplink and the downlink is important. This can be implemented by appropriately distributing the TDD synchronization signal transmitted from the base station or the mother relay system in the Tx / Tx Transition Gap (RTG) and Rx / Tx Transition Gap (RTG) intervals between the uplink and the downlink.

8 is a diagram illustrating a time relationship of a transmission / reception switching signal between an uplink and a downlink in a signal conversion apparatus for a wireless communication system according to the present invention.

Referring to FIG. 8, the WiBro time division multiplexing (TDD) signal has a TTG section of 87.2 ms between the uplink and the downlink, and has an RTG section of 74.4 ms between the downlink and the uplink. At this time, the minimum timing for preservation of the error vector magnitude (EVM) is 10 ms based on the start point and the end point of the TTG section, and 10 ms and 15 respectively based on the start point and the end point of the RTG section. . In addition, the reference signal of the Sync. Detection Module (SDM) maintains 'High' in the downlink period, and its error range is at most 1 dB. Under these conditions, 'high' and 'low' are alternated in the TTG and RTG intervals between the uplink and the downlink, and the transmit and receive alternating signals are 'high' and ' Low '. At this time, the state change point of the transmission / reception switch signal (ie, the point of change from 'High' to 'Low' and 'Low' to 'High') prevents the device from being damaged by controlling other devices in the system or by sudden switching. In order to do this, there is a certain delay from the state change of the WiBro TDD signal. This delay is set greater than the minimum timing for EVM retention in the TTG and RTG intervals. That is, the time point at which the transmission / reception switch signal is changed from 'High' to 'Low' in the TTG section should be 10 ㎲ away from the start point and the end point of the TTG section, preferably, the middle point of the TTG section. It is set to a time point of about 44 kHz from the time when the WiBro TDD signal is changed from 'High' to 'Low'. The same applies to the RTG section. The time point at which the transmission / reception signal is changed from 'Low' to 'High' in the RTG section is 10 ㎲ and 15 떨어진 away from the start and end points of the RTG section, respectively. Preferably, it is set to a time when the WiBro TDD signal, which is the time corresponding to the midpoint of the RTG section, becomes about 37 ms from the time when the TDD signal is changed from 'High' to 'Low'.

Although the preferred embodiments of the present invention have been shown and described above, the present invention is not limited to the specific preferred embodiments described above, and the present invention belongs to the present invention without departing from the gist of the present invention as claimed in the claims. Various modifications can be made by those skilled in the art, and such changes are within the scope of the claims.

1 is a diagram showing the configuration of a base station apparatus of a conventional time division multiplexing mobile communication system;

2 is a diagram showing the configuration of a first preferred embodiment of a signal conversion apparatus for a wireless communication system according to the present invention;

3 is a diagram showing the configuration of a second preferred embodiment of a signal conversion apparatus for a wireless communication system according to the present invention;

4 is a diagram showing the configuration of a third preferred embodiment of a signal conversion apparatus for a wireless communication system according to the present invention;

5 to 7 are views illustrating a state in which embodiments of the present invention described with reference to FIGS. 2 to 4 are applied to a TDD mobile communication digital relay system using a MIMO scheme.

8 is a diagram illustrating a time relationship of a transmission / reception switching signal between an uplink and a downlink in a signal conversion apparatus for a wireless communication system according to the present invention.

Claims (10)

A first switch switched between a first fixed side contact to which the first signal received from the mobile station is input and a second fixed side contact to which the second signal to be transmitted to the mobile station is input; A first bandpass filter for selectively filtering a frequency of a predetermined band from the first signal and the second signal; A first amplifier for amplifying and outputting a signal passing through the first band pass filter; A gain adjuster for adjusting the gain of the signal amplified by the first amplifier; And A first fixed side contact electrically connected to a demodulator for demodulating the signal output from the gain regulator to a switching center or base station and a second signal electrically connected to a transmission / reception antenna for transmitting a signal output from the gain regulator to a mobile station; And a second switch switched between the fixed side contacts. The method of claim 1, When the first signal received from the mobile station is input to the first band pass filter by the switching operation of the first switch, the second switch is switched to provide a signal output from the gain adjuster to the modulator. And when the second signal to be transmitted to the mobile station is input to the first bandpass filter by a switching operation of the first switch, the second switch is switched to provide a signal output from the gain adjuster to the transmit / receive antenna. Signal conversion device for wireless communication system. The method according to claim 1 or 2, And the first bandpass filter is a dielectric bandpass filter. The method according to claim 1 or 2, A first multiplier electrically connected to a second fixed side contact of the first switch; A second multiplier electrically connected to the first fixed side contact of the second switch; A local oscillator for providing a reference frequency signal to the first multiplier and the second multiplier; A third switch switched between a first fixed side contact electrically connected to the second multiplier and a second fixed side contact to which a second signal to be transmitted to the mobile station is input; A second amplifier for amplifying and outputting a signal input from the third switch; A second band pass filter for selectively filtering a frequency of a predetermined band from a signal input from the second amplifier; And a fourth switch switched between a first fixed side contact electrically connected to the demodulator and a second fixed side contact electrically connected to the first multiplier. The method of claim 4, wherein When the first signal received from the mobile station is input to the first bandpass filter by the switching operation of the first switch, the third switch is switched to provide a signal output from the second multiplier to the second amplifier. A signal conversion device for a wireless communication system, characterized in that. The method of claim 4, wherein And said second bandpass filter is a surface acoustic wave bandpass filter. The method according to claim 1 or 2, A local oscillator for outputting a reference frequency of a predetermined magnitude; A multiplier for multiplying the reference frequency by an input signal and outputting the multiplier; A third switch that is switched between a first fixed side contact and a second fixed side contact electrically connected to a second fixed side contact of the first switch to selectively output a signal input from the multiplier; A fourth switch switched between a first fixed side contact electrically connected to the first fixed side contact of the third switch and a second fixed side contact to which a second signal to be transmitted to the mobile station is input; A second amplifier for amplifying and outputting a signal input from the fourth switch; A second bandpass filter for selectively filtering a frequency of a predetermined band from a signal input from the second amplifier; A fifth switch switched between a first fixed side contact and a second fixed side contact electrically connected to the demodulator; And The first fixed side is switched between a first fixed side contact electrically connected to the first fixed side contact of the second switch and a second fixed side contact electrically connected to the second fixed side contact of the fifth switch. And a sixth switch for selectively outputting a signal inputted to a contact point or the second fixed side contact point to the multiplier. The method of claim 7, wherein When the first signal received from the mobile station is input to the first band pass filter by the switching operation of the first switch, the second switch to the sixth switch receive a signal input to each of the first fixed side contacts. A signal conversion device for a wireless communication system, characterized in that switched to output. The method of claim 7, wherein And said second bandpass filter is a surface acoustic wave bandpass filter. The method according to claim 1 or 2, The first switch and the second switch are input by delaying a predetermined time from an end point of an uplink period for transmitting a signal received from the mobile station to the switching center or base station and a downlink period for transmitting a signal from the switching station or base station to the mobile station. And the switching operation is performed by a switching signal.

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