KR100701976B1 - A wireless repeater with short delay characteristics - Google Patents

Abstract

The present invention relates to a wireless repeater having a low delay property.

The present invention is located between the transmitter or one repeater and the other repeater or the receiving terminal is installed in the repeater for relaying the received signal and the transmission signal, and has a short delay time (transmission signal transmitted and received through the transmission and reception antenna) And a wireless repeater which processes a received signal by a direct conversion method, filters and amplifies a specific frequency band of the transmitted signal and the received signal.

Accordingly, the present invention provides wireless communication to a terminal in a shaded area in a system that performs high-speed wireless communication such as CDMA (Code Division Multiple Access), CDMA2000, Wideband CDMA (WCDMA), Digital Multimedia Broadcasting (DMB), and Wireless Broadband Internet (WiBro). In the repeater which amplifies and repeats the signal, the system delay time generated in the repeater is shortened by processing and amplifying the transmission signal and the received signal transmitted and received through the transmission / reception antenna at high speed by the direct conversion method in the wireless repeater. It is effective to reduce the probability of noise or error related to the phase due to the high frequency error being '0', and stable delay margin between input and output of the repeater due to the low delay characteristic that shortens the system delay time. The quality deterioration caused by the deterioration of ISI (Inter Symbol Interference) appears slowly, The wider the frequency band, the easier it is to use a low frequency delay (Duplexer Filter, DPLX) and a band pass filter (BPF), which is advantageous in supporting broadband service.

Description

A WIRELESS REPEATER WITH SHORT DELAY CHARACTERISTICS}

1 is a block diagram showing the configuration of a conventional wireless relay device.

Figure 2 is a block diagram showing the configuration of a wireless repeater having a low delay property according to a first embodiment of the present invention.

Figure 3 is a block diagram showing the configuration of a wireless repeater having a low delay property according to a second embodiment of the present invention.

Figure 4 is a block diagram showing the configuration of a wireless repeater having a low delay property according to a third embodiment of the present invention.

5 is a graph showing the relationship between the isolation margin between the input and output of the repeater and the signal quality (EVM) in the wireless repeater having the low latency characteristics of the present invention.

6A and 6B are conceptual views illustrating output signal quality of a repeater according to a system delay time in a wireless repeater having a low latency characteristic of the present invention.

7 is a table showing the waveform quality (Rho) and the signal quality (EVM) according to the isolation margin in the wireless repeater having a low latency characteristic of the present invention.

FIG. 8 is a graph showing a waveform quality graphically using the data of FIG. 6 in a wireless repeater having a low latency characteristic of the present invention. FIG.

9 is a graph showing signal quality graphically using the data of FIG. 6 in the wireless relay device having the low latency characteristic of the present invention.

*** Description of the symbols for the main parts of the drawings ***

201,212: transmit and receive antenna

202,207: first and second low delay frequency separators

203,208: first and second low noise amplifier

204,209: first and second amplifiers

205,210: First and second low delay bandpass filters

206,211: first and second high power amplifiers

212-1,212-2: transmit and receive antennas

213,214: Third and fourth low delay bandpass filters

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication system, and more particularly, to a system that performs high-speed wireless communication such as code division multiple access (CDMA), CDMA2000, wideband CDMA (WCDMA), digital multimedia broadcasting (DMB), and wireless broadband Internet (WiBro). In the repeater which amplifies and relays a radio signal to a terminal in a shaded area, the radio repeater generates and amplifies by transmitting and amplifying a transmission signal and a reception signal through a direct conversion method at high speed by a direct conversion method. As the system delay time is shortened and the frequency error is '0', it is effective to reduce the probability of noise or error related to the phase.In addition, the isolation delay between the input and output of the repeater Isolation Margin is secured and quality deterioration is slowed due to deterioration of Inter Symbol Interference (ISI). The wider the filtered frequency band, the easier it is to use low frequency delay (Duplexer Filter, DPLX) and Band Pass Filter (BPF). It relates to a wireless repeater having a low delay property.

A repeater is a device that transmits a radio frequency (RF) signal of a base station to a remote area in various ways and regenerates it as an RF signal. In general, a repeater eliminates shaded areas that the RF signal of the base station cannot reach and provides service coverage. Refers to all systems installed inside or outside the base station (remote location) for the purpose of enlarging the coverage, and includes fiber optic repeaters, frequency conversion repeaters, Microwave repeaters, laser repeaters, micro repeaters, home repeaters, Interference Canceller repeaters, and in-builing repeaters.

The repeater is used for mobile communication service to handle mobile communication signal with weak field strength (RSSI) in both transmission and reception, while it is used for satellite DMB (Digita Multimedia Broadcasting) service to receive broadcast signal with low field strength. In addition, a gap filler which amplifies only a desired signal and retransmits in one direction may also be included in a repeater.

Meanwhile, the repeater includes a wireless repeater that receives and amplifies an RF signal from a transmitter or another repeater through a transmitting / receiving antenna, converts a frequency, and transmits the same to another repeater or a receiving terminal, as shown in FIG. In the wireless relay apparatus 100 according to the related art, the first and second frequency separators 116 and 117 for separating the frequency of the received / transmitted signal and the forward (i.e., between the first and second frequency separators 116 and 117). The first low noise amplifier 101, the first frequency mixer 102, the first filter 103, the first intermediate frequency amplifier 104, and the second frequency mixer, which perform signal processing from the transmitter to the receiving terminal direction). 105, a first high power amplifier 106, and the like, a second low noise amplifier 110, a third frequency separator 111, and a second filter performing signal processing in the reverse direction (i.e., from the receiving terminal to the transmitter). 112, second Like cross-frequency amplifier 113, and the fourth frequency mixer 114, a second high-power amplifier 115 is disposed.

Here, the first frequency mixer 102 receives a predetermined first local oscillation frequency through the first local oscillation frequency generator 107 and then mixes it with a signal traveling forward to generate an intermediate frequency signal. The filter 103 and the first intermediate frequency amplifier 104 filter and amplify and output only the frequencies of the desired signals with a narrow bandwidth, and the second frequency mixer 105 outputs a second local oscillation frequency. After receiving the second local oscillation frequency through the generator 109 and mixing it with the signal passed through the first intermediate frequency amplifier 104 to generate a high frequency signal, the generated high frequency signal to the second frequency separator 117 It transmits to another repeater or a receiving terminal through a transmission and reception antenna (4b).

By the action of the first and second frequency mixers 102 and 105, the weak signal at the transmitter side received by the transmit / receive antenna 4a is amplified and converted to a stable signal and then received. In this case, even if the receiving terminal is located in the shadow area, the signal output from the calling terminal can be normally transmitted to the receiving terminal.

Therefore, the conventional wireless repeater is designed in a super heterodyne manner as described above, and in this case, the surface acoustic wave, which is a component element having a delay time as large as 3 to 5 로 with the first and second filters 103 and 112. The overall system delay time is increased by using Surface Acoustic Wave Filter (SAW Filter). When the delay time of wireless repeater is longer, RF signal goes through repeater and Multi-PN (Pseudo Noise) signal is added. As the number of repeaters with this characteristic increases in the same cell, the noise floor increases, resulting in deterioration of overall cell quality and reduced capacity. The problem arises.

In addition, due to the frequency conversion and oscillation processes used in the conventional super heterodyne method, frequency error, phase noise, phase error, etc. are liable to occur in the signal output from the wireless repeater, causing a problem that the repeater performance is degraded. .

Accordingly, the present invention has been proposed to solve the above-described problems, and includes high speed, such as CDMA (Code Division Multiple Access), CDMA2000, Wideband CDMA (WCDMA), Digital Multimedia Broadcasting (DMB), and Wireless Broadband Internet (WBro). In a repeater that amplifies a radio signal to a terminal in a shaded area in a system performing wireless communication, the radio signal is processed by a direct conversion method at a high speed with a direct conversion method. It is an object of the present invention to provide a wireless repeater to amplify and reduce the system delay time generated in the repeater.

The present invention for achieving the above object is located between the transmitter or one repeater and the other repeater or the receiving terminal is installed in the repeater for relaying the received signal and the transmission signal, and has a short delay time characteristics The transmission and reception signals transmitted and received through the transmission and reception antennas are processed by a direct conversion method, so as to filter and amplify a specific frequency band of the transmission and reception signals.

In addition, the present invention has a short delay time (short delay time) characteristics, and the first and second low-delay frequency separator for separating the frequency of the transmission and reception signals transmitted and received through the transmission and reception antenna at high speed; First and second low noise amplifiers for minimizing and amplifying noise of the transmission signal and the reception signal separated by the first and second low delay frequency separators; First and second amplifiers for amplifying the outputs of the first and second low noise amplifiers to a predetermined level; First and second low delay bandpass filters having a low delay characteristic and rapidly filtering a specific band frequency by a direct conversion method of a transmission signal and a reception signal output through the first and second amplifiers. Band Pass Filter (BPF); And first and second high power amplifiers for amplifying the transmitted and received signals band-passed by the first and second low-delay bandpass filters to a high level for relaying.

In addition, the present invention has a low delay (short delay time) characteristics, and a low delay frequency separator for separating the frequency of the transmission and reception signals transmitted and received through the transmission and reception antenna at high speed; First and second low noise amplifiers for minimizing and amplifying noise of the transmission signal and the reception signal separated by the low delay frequency separator; First and second amplifiers for amplifying the outputs of the first and second low noise amplifiers to a predetermined level; First and second low delay bandpass filters having a low delay characteristic and rapidly filtering a specific band frequency by a direct conversion method of a transmission signal and a reception signal output through the first and second amplifiers. Band Pass Filter (BPF); First and second high power amplifiers for amplifying the transmitted and received signals band-passed in the first and second low-delay bandpass filters to a high level for relaying; Transmitting and receiving antennas for transmitting and receiving transmission and reception signals through separate paths; A third low delay bandpass filter for filtering the received signal amplified by the first high power amplifier at high speed by direct conversion and outputting the specific signal to the transmitting antenna; And a fourth low delay bandpass filter which filters only a specific band frequency at a high speed by a direct conversion method and transmits the signal transmitted through the reception antenna to the second low noise amplifier.

In addition, the present invention provides a short delay time in a wireless repeater for transmitting a received signal from a transmitter or one repeater to another repeater or a receiving terminal when performing a unidirectional digital multimedia broadcasting (DMB) service. A first low delay bandpass filter having a characteristic, and fast filtering only a specific frequency by a direct conversion method on a received signal received from a transmitter or one repeater through a receiving antenna; An amplifier for amplifying the output of the first low delay bandpass filter to a predetermined level; A second low delay bandpass filter having a low delay characteristic and filtering the received signal output through the amplifier at a high speed by a direct conversion method; A high power amplifier for amplifying the received signal band-passed at the second low delay bandpass filter to a high level for relaying; It has a low delay characteristics, and characterized in that it comprises a third low delay bandpass filter for transmitting the output of the high-power amplifier to the other repeater or the receiving terminal through the transmitting antenna.

Hereinafter, a first embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a block diagram showing a configuration of a wireless repeater having a low delay property according to a first embodiment of the present invention. As shown in FIG. 2, a signal is placed between a transmitter or one repeater and another repeater or a receiving terminal. It is installed inside a repeater for transmitting a transmission signal, and has a short delay time characteristic to process the transmission and reception signals transmitted and received through the transmission and reception antennas 201 and 212 by a direct conversion method, the transmission A wireless repeater 200 filters and amplifies a specific frequency band of a signal and a received signal.

More specifically, the first and second low delay frequency separators 202 and 207 having a short delay time characteristic and rapidly separating frequencies of transmission and reception signals transmitted and received through the transmission and reception antennas 201 and 212. ; First and second low noise amplifiers (203, 208) for minimizing and amplifying noise of the transmitted and received signals separated by the first and second low delay frequency separators (202, 207); First and second amplifiers (204, 209) for amplifying the outputs of the first and second low noise amplifiers (203, 208) to a predetermined level; First and second low delay bands having a low delay characteristic and rapidly filtering a specific band frequency by a direct conversion method of a transmission signal and a reception signal output through the first and second amplifiers 204 and 209. A band pass filter (BPF) 205 and 210; And first and second high power amplifiers 206 and 211 which amplify the transmitted and received signals band-passed by the first and second low delay bandpass filters 205 and 210 to a high level for relaying.

Through the above configuration, the present invention is shaded in a system that performs high-speed wireless communication such as Code Division Multiple Access (CDMA), CDMA2000, Wideband CDMA (WCDMA), Digital Multimedia Broadcasting (DMB), and Wireless Broadband Internet (WiBro). In the repeater for amplifying and relaying a radio signal to a local terminal, the super repeater by amplifying a high-speed transmission and reception signal transmitted and received through a transmission and reception antenna in a wireless conversion apparatus by a direct conversion method, The system delay time is shortened by overcoming the system delay time, frequency distortion, frequency error, phase noise, phase error, etc. which occurred in the process of internally converting the frequency of the transmission signal and the radio signal in the super heterodyne method. The frequency error will be '0', reducing the probability of noise or errors associated with the phase. In addition, due to the low latency of the system delay time, the stability of the isolation margin between the input and output of the repeater is secured, resulting in a smooth degradation of the quality due to the deterioration of ISI (Inter Symbol Interference). The wider the band delay filter (DPLX) and the band pass filter (BPF) with low delay characteristics, the easier it is to support broadband service.

The repeater to which the present invention is applied can be applied to a system that performs high-speed wireless communication such as CDMA (Code Division Multiple Access), CDMA2000, Wideband CDMA (WCDMA), Digital Multimedia Broadcasting (DMB), and Wireless Broadband Internet (WiBro). Located between a transmitter (for example, a base station, etc.) or one repeater and the other repeater or the receiving terminal, amplifies and relays the received signal and the transmitted signal to the receiving terminal in the shadow area through the transmitting and receiving antennas 201 and 212. do. Here, the repeater includes a transmitting and receiving antenna (201, 212) for transmitting and receiving a radio signal, such as a transmitter, another repeater, a receiving terminal, a GPS antenna for receiving a GPS signal from a GPS (Global Positioning System) satellite, GPS A GPS module for processing a signal may optionally be provided.

The receiving terminal refers to a communication terminal supporting wireless communication such as a mobile communication terminal, a PDA (Personal Digital Assistants), a notebook computer, and is named for description according to the forward direction (from the transmitter to the receiving terminal direction). In the case of performing signal processing according to the transmitter from the side terminal (except in the case of a terminal supporting unidirectional DMB service), the terminal may be referred to as a transmitting terminal.

The wireless repeater 200 of the present invention installed in the repeater serving as described above has a short delay time characteristic and directly converts a transmission signal and a reception signal transmitted and received through the transmission and reception antennas 201 and 212. It processes by the conversion method, and filters and amplifies a specific frequency band of the transmission signal and the reception signal.

Most of the system delay time that occurs in the repeater is generated in the low delay frequency separators 202 and 207 and the low delay bandpass filter 205 and 210 of the wireless repeater 200. Among them, the low delay frequency separators 202 and 207 In the case of the low delay bandpass filters 205 and 210, the delay time is about several tens to several hundreds of microseconds (about 50 to 300 ns), respectively. The low delay frequency separators 202 and 207 and the low delay bandpass filters 205 and 210 are mainly used. Since the overall system delay time is determined by the present invention, in the present invention, the low delay characteristics are implemented by using the low delay frequency separators 202 and 207 and the low delay bandpass filters 205 and 210 that enable high-speed data processing. To reduce the system delay time that occurs at (200).

In particular, the wireless relay apparatus 200 of the present invention has a low delay frequency separator 202, 207 and a low delay bandpass filter 205, 210 that set system delay time required to process a transmission signal and a reception signal within a transmission time of unit data. Low delay characteristics can be implemented using, for example, in the case of the CDMA scheme, a chip which is unit data of a signal spread by spreading the system delay time required for processing a transmission signal and a reception signal in the wireless relay device 200. Low delay characteristics are implemented using the low delay frequency separators 202 and 207 and the low delay bandpass filters 205 and 210 that can be set within the transmission time.

Further, according to the present invention, the transmission and reception signals transmitted and received by the wireless relay device 200 are processed by a direct conversion method, whereby the frequency of the transmission and reception signals input and output to the wireless relay device 220. The error is '0 Hz'.

Meanwhile, in the first embodiment of the present invention, when the wireless relay apparatus 200 forwards a received signal received from a transmitter (for example, a base station, etc.) to a receiving terminal, a low delay (short) In the first low delay frequency separator 202 having a delay time characteristic, a frequency of a received signal received from a transmitter or a repeater through a transmission / reception antenna 201 is separated at a high speed, and thus, the first low noise amplifier 203 The first low delay frequency separator 202 minimizes and amplifies the noise of the received signal, and the first amplifier 204 amplifies the output of the first low noise amplifier 203 again to a predetermined level.

Then, the first low delay bandpass filter 205 having a low delay characteristic filters the received signal output through the first amplifier 204 through a direct conversion method at high speed, and then, The first high-power amplifier 206 amplifies and outputs the received signal band-passed by the first low delay bandpass filter 205 to a high level for relaying, and thus, similarly to the first low delay frequency separator 202. The second low delay frequency separator 207 having the low delay characteristic transmits the output of the first high power amplifier 206 to the other repeater or the receiving terminal through the transmission and reception antenna 212.

Here, the wireless relay device 200 performs a reverse process of transmitting a transmission signal transmitted from a receiving terminal to a transmitter (for example, a base station) in addition to the forward processing as described above. The second low noise amplifier 208, the second amplifier 209, the second low delay bandpass filter 210, the second high power amplifier 211, or the like, between the first and second low delay frequency separators 202 and 207. Although the specific operation of each component is the same as that of the forward process, a description of the operation of the reverse process will be omitted.

On the other hand, the wireless repeater having the second embodiment low latency characteristic of the present invention, as shown in Fig. 3, instead of the second low delay frequency separator 207 in the configuration of the first embodiment of the present invention, The receiving end is separated and configured by adding third and fourth low delay bandpass filters 213 and 214, a transmitting antenna 212-1 and a receiving antenna 212-2 connected thereto.

For example, if the frequency interval between the Tx band and the Rx band is close, such as a CDMA service in the 800 MHz band, the high power is generated in the first high-power amplifier 206 located at the end of the forward processing path (Tx path), thereby causing an IMD (Inter Modulation Distortion Induces a phenomenon in which a signal appears in a reverse processing path (Rx path), that is, an interference phenomenon.

Accordingly, in the second embodiment of the present invention, the third and fourth low-delay bandpass filters 213 and 214, a transmission antenna 212-1 and a reception antenna 212-2 connected thereto are provided to provide the forward processing path ( Tx path) prevents the IMD component from interfering with the Rx band, and for this purpose, a forward processing path (Tx path) for processing a received signal received from a transmitter or one repeater and transmitting it to the other repeater or the receiving terminal. And the reverse processing path (Rx path) for processing the transmission signal transmitted from the other repeater or the receiving terminal to the transmitter or one repeater.

That is, the third and fourth low delay bandpass filters 213 and 214 respectively filter the received signals and the transmitted signals through the forward processing path (Tx path) and the reverse processing path (Rx path), and the forward processing path (Tx path). In the operation of the other components are the same as the first embodiment of the present invention, in the operation of the third low-delay bandpass filter 213, according to the forward processing path (Tx path), the first high power amplifier 206 ), The received signal amplified to a high level for relaying at high speed is filtered directly at a specific band frequency by a direct conversion method and transmitted to the other repeater or the receiving terminal through the transmitting antenna 212-1. .

In addition, the fourth low-delay bandpass filter 214 filters only a specific band frequency at a high speed by using a direct conversion method on a transmission signal received through the reception antenna 212-2 according to a reverse processing path (Rx path). Output to the second low noise amplifier 208, where the fourth low delay bandpass filter 214 prevents harmonic signals generated when the amplified transmission signal is amplified as well as a specific band frequency to be amplified. It serves to prevent amplification of other frequency band signals.

Here, the low delay characteristics of the third and fourth low delay bandpass filters 213 and 214 are the same as those of the first and second low delay bandpass filters 205 and 210.

On the other hand, the wireless relay device having a low delay property according to the third embodiment of the present invention, as shown in Figure 4, can be applied to a one-way digital multimedia broadcasting (DMB) service, in this case the wireless of the present invention The relay apparatus 200 performs only forward processing of transmitting a received signal received from a transmitter (for example, a base station) or one repeater to another repeater or a receiving terminal.

That is, in a first low delay bandpass filter 402 having a short delay time characteristic, a received frequency received from a transmitter or a repeater through a receiving antenna 401 is directly converted into a specific frequency. Filters the bay at high speed, detects the received signal while performing operations similar to those when receiving the received signal in the low delay frequency separators 202 and 207, and thereby the first low delay bandpass filter 402 in the amplifier 403. Amplifies the output to a predetermined level.

Then, the second low delay bandpass filter 404 having a low delay characteristic filters the received signal output through the amplifier 403 at high speed by a second direct conversion method at high speed, and then a high power amplifier ( In 405, the second low-delay bandpass filter 404 amplifies and outputs the received signal that is band-passed to a high level for relaying, and thus has low latency characteristics similar to that of the first low-delay bandpass filter 402. The third low delay bandpass filter 406 transmits the output of the high power amplifier 405 to the other repeater or the receiving terminal through the transmitting antenna 407.

Here, in the first and second embodiments of the present invention, the low delay frequency separators 202 and 207 are coupled to the antennas 401 and 407 by combining a low delay bandpass filter for transmission and a low delay bandpass filter for reception. In the case of the unidirectional DMB service, only the signal processing in the forward direction needs to be performed. Therefore, the first and third low delay bandpass filters 402 and 407 are installed in place of the low delay frequency separators 202 and 207.

The low delay characteristics of the first to third low delay bandpass filters 402, 404 and 407 are the same as those of the low delay bandpass filter in the first and second embodiments of the present invention, thereby processing the received received signal. The delay time is set within the transmission time required to transmit unit data in the system (repeater).

In general, the system delay time required for processing the received signal and the transmitted signal in the wireless relay 200 is closely related to the quality of service of the repeater and the isolation margin between input and output between the transmitting and receiving antennas 201 and 212. As the system delay time is shortened, the operating margin for oscillation increases.

Therefore, the wireless relay apparatus 200 according to the present invention uses a direct conversion method using a low delay frequency separator 202 and 207 having a low delay characteristic and a low delay bandpass filter 205 and 209 without frequency conversion. By using the surface acoustic wave filter (SAW Filter) in the conventional super heterodyne system, the system delay time is improved by compensating for the disadvantage that the overall system delay time is long, and filtering the received signal and the radio signal at high speed. The effect of shortening is obtained.

For example, as shown in the graph showing the relationship between the I / O isolation margin and the signal quality (Error Vector Magnitude, EVM) shown in Fig. 5, the conventional super heterodyne repeater is more than one chip (typically). Isolation margin between input and output according to the communication protocol is required to be at least 15 to 20 dB or more (corresponding to graph (2)), but the direct conversion according to the present invention is achieved. In the CDMA method, the repeater has a delay time within the transmission time (813 ms) of one chip, which is the unit data of the spread signal, and can be set such that the isolation margin between input and output is 10 dB or less (graph ( 1)), in the environment with sufficient isolation margin as shown in area (a), there is no difference in signal quality (EVM) characteristics between the conventional and the repeater according to the present invention. In the environment where the margin is insufficient, the operating margin and quality stability of the oscillation are weak due to the occurrence of back margin and deterioration of ISI in the repeater according to the conventional method, whereas in the repeater according to the present invention, the margin between input and output is decreased. Even if it is small, the quality deterioration due to ISI deterioration is moderate, indicating that the operating margin and quality stability against oscillation are excellent.

6 is a conceptual diagram showing the output signal quality of the repeater according to the system delay time, showing the concept that the quality and capacity of the output signal is improved due to the short system delay time in the repeater according to the present invention.

That is, the repeater according to the conventional super heterodyne method as shown in FIG. 6A has a system delay time of more than 1 chip (generally, about 1 to 5 dB or more). The interference signal increases due to the additional generation of Multi-PN (Pseudo Noise) signal, and as the number of repeaters having such characteristics increases in the same cell, the noise floor increases. As a result, the quality of the reverse path of the transmitter is degraded as a whole and the capacity is reduced.

However, as shown in FIG. 6B, the repeater according to the present invention has a system delay time of about 1 chip (813 ns in the case of the CDMA method), which is about several times faster than the conventional super heterodyne method. Since the output signal by is operated as a dynamic signal which is almost the same as the original PN signal input to the repeater and does not act as an interference signal, the noise floor does not rise, thereby minimizing the quality degradation and capacity reduction of the entire cell. Done.

8 is a table showing waveform quality (Rho) and signal quality (EVM) according to the isolation margin. In the CDMA system, the repeater according to the present invention has an input power of -70 dBm / 1.25 MHz, a gain of 95 dB, and an output. When the power of + 25dBm / 1.25MHz, and the conventional super heterodyne repeater, the input power -68dBm / 1.25MHz, gain 58dB, the output power -10dBm / 1.25MHz, and experimented with the meter, the isolation margin '30dB In both the present invention and the prior art, the waveform quality (Rho) is similar to '0.998' and '0.996', but the isolation margin is increased as the present invention is '0.990' and the conventional '0.9202' at the isolation margin of '10dB'. According to the present invention, it can be seen that the waveform quality Rho of the repeater according to the present invention is excellent, which can be confirmed through the graph diagram of FIG. 8 in which the data displayed in the table diagram of FIG. 7 is graphed.

In the comparison of the signal quality (EVM), in the present invention, the signal quality (EVM) is maintained at '10 .6% 'at the isolation margin' 9dB ', but in the conventional case, the '10 .0%' at the isolation margin '21dB' is obtained. In terms of maintaining, the repeater according to the present invention can be seen that the signal quality (EVM) is superior to the conventional repeater, which can be confirmed through the graph of FIG. 9 graphically showing the data displayed in the table of FIG. Can be.

In addition, in the case of the low delay frequency separators 202 and 207 and the low delay bandpass filter 205 and 210 having low delay characteristics, the delay time required for processing an input signal is generally shorter as the frequency band is wider. Repeater applied to is advantageous for wireless communication service supporting wideband. In the present invention, since the frequency conversion is not performed, it is also possible to connect two or more repeaters in series when the present invention is applied to the outdoor wireless relay system.

As described above, the present invention provides a shadow area in a system that performs high-speed wireless communication such as Code Division Multiple Access (CDMA), CDMA2000, Wideband CDMA (WCDMA), Digital Multimedia Broadcasting (DMB), and Wireless Broadband Internet (WiBro). In the repeater for amplifying and relaying a radio signal to a terminal of the terminal, the super repeater by amplifying a high-speed transmission and reception signal transmitted and received through a transmission and reception antenna in a direct conversion method by a direct conversion method, The system delay time is shortened by overcoming the increase of system delay time, frequency distortion, frequency error, phase noise, phase error, etc. that occurred in the process of internally converting the frequency of the transmission signal and the radio signal in the (Super Heterodyne) method. The frequency error is '0', which reduces the probability of generating noise or errors related to the phase.

In addition, due to the low latency of the system delay time, the stability of the isolation margin between the input and output of the repeater is secured, resulting in a smooth degradation of the quality due to the deterioration of ISI (Inter Symbol Interference). The wider the band delay filter (DPLX) and the band pass filter (BPF) with low delay characteristics, the easier it is to support broadband service.

Claims (11)

Located between the transmitter or one repeater and the other repeater or the receiving terminal, it is installed inside the repeater for relaying the received signal and the transmitted signal, and has a short delay time characteristic. Is processed by a direct conversion method, the wireless repeater having a low delay characteristics, characterized in that the filter and amplifies a specific frequency band of the transmission signal and the reception signal. The low latency characteristic of claim 1, wherein the low latency characteristic is implemented by setting a system delay time required for processing a transmission signal and a reception signal in a wireless relay device within a transmission time of unit data in a corresponding system. Wireless repeater having a. The chip of claim 1, wherein the low latency characteristic corresponds to a system delay time required for processing a transmission signal and a reception signal in a wireless relay device corresponding to unit data of a signal spread in a corresponding system. Wireless relay device having a low delay characteristics, characterized in that the implementation within the transmission time of). The low latency of any one of claims 1 to 3, wherein the low delay characteristics are implemented using a frequency divider filter (DPLX) or a band pass filter (BPF). Wireless repeater having the characteristics. The wireless repeater of claim 1, wherein the transmission signal and the reception signal have a frequency error of '0 Hz' before and after input. In the wireless repeater located between the transmitter or one repeater and the other repeater or the receiving terminal, and installed inside the repeater for relaying the received signal and the transmitted signal, First and second low delay frequency separators having a short delay time characteristic and rapidly separating frequencies of transmission and reception signals transmitted and received through a transmission and reception antenna; First and second low noise amplifiers for minimizing and amplifying noise of the transmission signal and the reception signal separated by the first and second low delay frequency separators; First and second amplifiers for amplifying the outputs of the first and second low noise amplifiers to a predetermined level; First and second low delay bandpass filters having a low delay characteristic and rapidly filtering a specific band frequency by a direct conversion method of a transmission signal and a reception signal output through the first and second amplifiers. Band Pass Filter (BPF); And a first and a second high power amplifier for amplifying a high level for transmitting and receiving a signal that is band-passed in the first and second low delay bandpass filters. Device. 7. The method of claim 6, wherein the first and second low delay bandpass filters have a delay time for processing the input transmission signal and the reception signal, the transmission time required for transmitting the unit data in the repeater, or the CDMA scheme. In the case of the wireless repeater having a low-delay characteristics characterized in that it is set within the transmission time required to transmit a chip (chip) corresponding to the unit data of the spread signal. In the wireless repeater located between the transmitter or one repeater and the other repeater or the receiving terminal, and installed inside the repeater for relaying the received signal and the transmitted signal, A low delay frequency separator having a short delay time characteristic and rapidly separating frequencies of transmission and reception signals transmitted and received through a transmission and reception antenna; First and second low noise amplifiers for minimizing and amplifying noise of the transmission signal and the reception signal separated by the low delay frequency separator; First and second amplifiers for amplifying the outputs of the first and second low noise amplifiers to a predetermined level; First and second low delay bandpass filters having a low delay characteristic and rapidly filtering a specific band frequency by a direct conversion method of a transmission signal and a reception signal output through the first and second amplifiers. Band Pass Filter (BPF); First and second high power amplifiers for amplifying the transmitted and received signals band-passed in the first and second low-delay bandpass filters to a high level for relaying; Transmitting and receiving antennas for transmitting and receiving transmission and reception signals through separate paths; A third low delay bandpass filter for filtering the received signal amplified by the first high power amplifier at high speed by direct conversion and outputting the specific signal to the transmitting antenna; And a fourth low delay bandpass filter for filtering the transmission signal received through the reception antenna at a high speed by directly converting a specific band frequency to the second low noise amplifier. Repeater. 9. The method of claim 8, wherein the first to fourth low-delay bandpass filters, the delay time for processing the input transmission signal and the received signal, the transmission time required to transmit the unit data in the repeater, or CDMA scheme In the case of the wireless repeater having a low-delay characteristics characterized in that it is set within the transmission time required to transmit a chip (chip) corresponding to the unit data of the spread signal. Located between the transmitter or one repeater and the other repeater or the receiving terminal, it is installed inside the repeater for relaying the received signal and the transmitted signal, and received from the transmitter or the repeater when performing one-way DMB (Digital Multimedia Broadcasting) service. In a wireless repeater for transmitting a received signal to another repeater or a receiving terminal, A first low delay bandpass filter having a short delay time characteristic and filtering the received signal received from the transmitter or one repeater through a receiving antenna at a high speed in a direct conversion scheme; An amplifier for amplifying the output of the first low delay bandpass filter to a predetermined level; A second low delay bandpass filter having a low delay characteristic and filtering the received signal output through the amplifier at a high speed by a direct conversion method; A high power amplifier for amplifying the received signal band-passed at the second low delay bandpass filter to a high level for relaying; And a third low delay bandpass filter for transmitting the output of the high power amplifier to the other repeater or the receiving terminal through a transmitting antenna. The apparatus of claim 10, wherein the first to third low-delay bandpass filters set a delay time for processing the received received signal within a transmission time required for transmitting the unit data in the repeater. Wireless repeater having a low delay property.

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