KR101022271B1 - Repeater - Google Patents

Abstract

The present invention has been devised to effectively handle multiple antenna technology in a relay device. As the mobile communication technology has gradually developed from voice communication to data communication, there has been a need for accommodating various techniques for data communication. Representative technologies corresponding thereto include transmit / receive diversity technology and MIMO technology. In the existing communication system, since the reception diversity technique is limited, it is easy to accommodate the relay apparatus, but as the system is developed in the direction of increasing the number of antennas, an efficient signal processing is required for the relay apparatus. The present invention is implemented so that the structure of the relay device is not complicated while improving the performance of the mobile communication system in the relay device.

Diversity, MIMO

Description

Repeater {REPEATER}

The present invention relates to a relay device, and more particularly, to a relay device made to effectively handle multiple antenna technology with one antenna in the relay device.

In general, a relay device is located between a base station and a terminal and transmits a downward (hereinafter referred to as 'down' or 'forward') signal of the base station to the terminal, and the terminal (hereinafter, referred to as 'upward' or 'reverse'). By relaying the signal to the base station, it is used for shadow area resolution and coverage extension. Therefore, the relay apparatus should be designed in consideration of the characteristics of the base station and the terminal in order to effectively transmit the signals of the base station and the terminal. Among them, transmit / receive diversity and MIMO signals are used by the base station and the terminal to improve the performance of a communication system in various situations in which one or more antennas are generated in a wireless channel.

This is called multi-antenna technology. Multiple antenna technologies include receive antenna diversity, transmit antenna diversity, and MIMO spatial multiplexing (SM) technology.

Diversity technology makes the signal you want to send a plurality of identical signals and transmits them on channels that are considered to have different propagation characteristics on the time axis, on frequency, or in space, and sometimes on antenna polarization, so that they are different on the receiving side. It is a technology that ensures more reliable reception by using signals from specific channels. Diversity techniques are called transmit diversity using the transmitting side and called diversity using the receiving side.

Receive diversity is a technique widely used in a communication system using a CDMA technology. The reception signal to noise ratio (SNR) is maximized by using one more reception antenna to increase reception performance. Transmit diversity, also known as space time coding, is a technique for compensating for signal degradation caused by transmission using two transmission antennas and two reception antennas. In order to apply the reception diversity or the transmission diversity to the relay device, a signal path must be prepared by the number of antennas. For example, since CDMA uses receive diversity in a 1Tx / 2Rx system, three paths, that is, Tx, Rx0, and Rx1, are required to make a CDMA relay, as shown in FIG. Previously, the relay device had inconveniences or disadvantages in preparing a path as many as the number of antennas of the system.

MIMO stands for Multi-input Multi-output and is a technology that improves the performance of a system by using a plurality of antennas on both a transmitting side and a receiving side. In a similar channel, even if a plurality of antennas are used, different data cannot be transmitted. However, if there are many reflected waves on the wireless channel and a high signal-to-noise ratio (SNR), the data rate can be increased by demodulating several data at the same time on the receiver side. In other words, MIMO technology is a technology for improving information transmission capability with multiple antennas while using the same space, the same frequency, and the same time. As mentioned above, the channel characteristics of the antennas are different from each other due to the reflected waves, so that when the channel matrix is formed as in Equation 1 below, different information can be simultaneously transmitted.

(식 1)

(Equation 1)

However, if the wireless channel environment is mainly a line of sight, the values of h11, h12, h21, and h22 in Equation 1 are similar to each other, so that signals are transmitted in the same space at the same time, so that signal transmission is smooth. I can't. In other words, a suitable environment for MIMO technology to take effect is an environment with more reflected waves than an environment where direct waves dominate.

In the existing repeater, ports of the repeater were prepared to match the number of input ports and output ports to process MIMO signals. For example, if a 2x2 MIMO signal is processed, the relay device prepares two input ports and two output ports as shown in FIG. 2 and prepares a path suitable for each input and output. That is, since 2x2 MIMO is a 2Tx / 2Rx system, four paths were prepared as Tx0, Tx1, Rx0, and Rx1.

In summary, in the existing repeater, whether it is diversity technology or MIMO technology, input ports and output ports are prepared for each antenna number, and paths are prepared. However, when the relay device is developed as described above, the internal structure of the relay device becomes more complicated as the number of antennas increases. It is not impossible to process signals from multiple antennas by using a conventional repeater system that transmits signals through output antennas by simply amplifying the input signal with less distortion as possible without processing any signal in the repeater, but the internal complexity is complicated. It was one of the reasons for the increase in equipment, manufacturing cost such as material cost increases.

The present invention was devised to solve the above problems, and although the relay apparatus has one forward output antenna (reverse input antenna), the relay apparatus can effectively implement the multi-antenna technique, that is, the transmit / receive diversity and MIMO technique, It is an object of the present invention to provide a relay device which does not complicate the internal structure of the device. In other words, unlike conventional relays, whether a diversity technique or a MIMO technique, the relay apparatus does not need to prepare an input port and an output port for each antenna number, and does not need to prepare a path separately. The purpose is to provide.

In order to achieve the above object, according to an aspect of the present invention, n forward input antenna for receiving the forward signal of the base station; M reverse output antennas for transmitting reverse signals to the base station; Front end unit; A forward multiple signal processor which processes a forward signal received from the forward input antenna and transmits the forward signal to the front end unit; A reverse multiple signal processor for processing a reverse signal received from the front end unit and transmitting the reverse signal to the reverse output antenna; And a forward output antenna configured to exchange forward and reverse signals with the front end unit, transmit a forward signal to a terminal, and receive a reverse signal from the terminal.

The forward multiple signal processor includes a separate forward signal processor for each of the n forward input antennas, and a forward time delay unit for delaying a signal from the forward signal processor, and outputs from the forward time delay unit. And a combiner for combining the n forward signals.

The reverse multi-signal processing unit may further include a splitting unit that separates the same m signals as the input signal through a signal input to the reverse multi-signal processing unit, and time delay is applied to the reverse signal from the separating unit. A reverse time delay section for processing a signal from the reverse time delay section.

On the other hand, according to another aspect of the invention, the n forward input antenna for receiving the forward signal of the base station; M reverse output antennas for transmitting reverse signals to the base station; A first forward multiple signal processor for processing the forward signal received from the forward input antenna and transmitting the processed forward signal to a framer / reframer, a first framer / reframer, and received from the first framer / reframer A main hub unit (MHU) including a first reverse multiple signal processor for processing one reverse signal and transmitting the reverse signal to the reverse output antenna; A second framer / reframer that exchanges a forward signal and a reverse signal with the first framer / reframer, a front end unit, and a forward signal received from the second framer / reframer to the front end unit. A second forward multiple signal processor for transmitting a second backward multiple signal processor for processing the backward signal received from the front end unit and transmitting the signal to the second framer / reframer; Unit (RU); And a forward output antenna configured to exchange forward and reverse signals with the front end unit, transmit a forward signal to a terminal, and receive a reverse signal from the terminal.

The first forward multiple signal processing unit and the second forward multiple signal processing unit each include a separate forward signal processing unit for each of the n forward input antennas, and a forward direction for delaying a signal from the forward signal processing unit. It has a time delay unit, and has a coupling unit for combining the n forward signals output from the forward time delay unit.

In addition, the first reverse multiple signal processing unit and the second reverse multiple signal processing unit may each be the same as the input signal through a signal input to the first reverse multiple signal processing unit and the second reverse multiple signal processing unit. A separation unit for separating into four signals, a reverse time delay unit for time delaying the reverse signal from the separation unit, and a reverse signal processing unit for processing signals from the reverse time delay unit.

On the other hand, according to another aspect of the present invention, n forward input antenna for receiving the forward signal of the base station; M reverse output antennas for transmitting reverse signals to the base station; A first forward multiple signal processor for processing the forward signal received from the forward input antenna and transmitting the processed forward signal to a framer / reframer, a first framer / reframer, and received from the first framer / reframer A main hub unit (MHU) including a first reverse multiple signal processor for processing one reverse signal and transmitting the reverse signal to the reverse output antenna; A second framer / reframer that exchanges a forward signal and a reverse signal with the first framer / reframer, a front end unit, and a forward signal received from the second framer / reframer to the front end unit. A remote unit comprising a second forward multiple signal processor for transmitting and a second reverse multiple signal processor for processing the reverse signal received from the front end unit and transmitting the signal to the second framer / reframer (RU); And a forward output antenna configured to exchange forward and reverse signals with the front end unit, to transmit a forward signal to a terminal, and to receive a reverse signal from the terminal. The two forward multiple signal processing sections each have a separate forward signal processing section for each of the n forward input antennas, and a forward time delay section for delaying a signal from the forward signal processing section, and outputs from the forward time delay section. And a combiner configured to combine the n forward signals, wherein the first reverse multiple signal processor and the second reverse multiple signal processor are respectively input to the first reverse multiple signal processor and the second reverse multiple signal processor. Through to separate into m signals equal to the input signal Has a separation unit, and provides a relay apparatus having a reverse time delay unit for time delaying the reverse signal from the separation unit, and a reverse signal processing unit for processing a signal from the reverse time delay unit.

It is also possible to use only max (m, n) antennas for the n forward input antennas and the m reverse output antennas.

In addition, each of the forward time delay units of the forward multiple signal processor, the first forward multiple signal processor, and the second forward multiple signal processor, may be delayed by a predetermined time different from each other.

The reverse time delay units of the reverse multiple signal processor, the first reverse multiple signal processor, and the second reverse multiple signal processor may each be delayed by an arbitrary time different from each other.

In addition, in order to be suitable for various mobile communication systems and multi-antenna technology, prepare as many input ports as the number of antennas at the input of the relay device, and combine the signals for each port similarly to the wireless channel environment in the multi-signal processing unit, and relay them. A method for transmitting to the output of the device and outputting the combined signal through one antenna, to maximize the effect of the multiple antenna technology and to simplify the internal structure of the relay device.

According to the relay device according to an embodiment of the present invention, even if the relay device has one forward output antenna (reverse input antenna), the relay device internal structure may be effectively implemented while the multi-antenna technology, that is, transmit / receive diversity and MIMO technology is effectively implemented. It is possible to provide a relay device that does not complicated.

In other words, unlike in the conventional relay device, whether it is diversity technology or MIMO technology, there is no need to prepare an input port and an output port for each antenna number, and there is no need to prepare a path separately. Has

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the present specification and claims should not be construed as being limited to the common or dictionary meanings, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that it can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

First, a first embodiment of the present invention will be described with reference to FIG. The relay apparatus 10 of the present invention includes n forward input antennas (not shown) for receiving the forward signals of the base station, m reverse output antennas (not shown) for transmitting the backward signals to the base station, and a forward multiple signal processor. (Tx) 11, a front end unit 13, a reverse multiple signal processor (Rx) 12, and one forward output antenna (i.e., a reverse input antenna) 14.

Here, since the forward input antenna and the reverse output antenna can be used in duplicate, it is a matter of course that only max (m, n) may be required. In addition, the base station 20 and the relay device 10 may be connected to each other by wire, for example, connected by an optical cable, and may be wirelessly connected. In addition, the front end unit 13 is responsible for distinguishing the forward signal of the base station and the reverse signal of the terminal, it is made of a filter in the frequency division duplexing (FDD) method, in the time division duplexing (TDD) method It consists of filter and RF switch.

Next, referring to Fig. 5, a second embodiment of the present invention will be described. The relay apparatus 100 of the present invention includes n forward input antennas (not shown) for receiving the forward signals of the base station, m reverse output antennas (not shown) for transmitting the backward signals to the base station, and a main hub unit ( MHU) 300, a remote unit (RU) 400, and one forward output antenna (ie, reverse input antenna) 500, where the main hub unit 300 is the first forward multiple signal processor 310. ) And a first reverse multiple signal processor 320 and a first framer / reframer 330, and the remote unit 400 also includes a second framer / reframer 430. ), A second forward multiple signal processor 410, a second reverse multiple signal processor 420, and a front end unit 440.

Here, since the first framer / reframer 330 and the second framer / reframer 430 use known techniques, description thereof will be omitted. In addition, the base station 200 and the relay device 100 may be connected to each other by wire, for example, connected by an optical cable, and may be wirelessly connected. In addition, as described above, the front end unit 13 in this case is responsible for the function of distinguishing the forward signal of the base station and the reverse signal of the terminal, in the FDD (Frequency Division Duplexing) scheme is made of a filter, TDD (Time Division Duplexing) consists of a filter and an RF switch.

In addition, as shown in Fig. 6, the forward multiplex signal processing section (Tx) 11 of the first embodiment of the present invention includes a separate forward signal processing section for each of the n forward input antennas, and the forward signal processing section from the forward signal processing section. A forward time delay unit for delaying a signal, and a coupling unit for coupling n forward signals outputted from the forward time delay unit, and on the other hand, a first forward multiple signal processor 310 of the second embodiment of the present invention. And the second forward multiple signal processing section 410 each have a separate forward signal processing section for each of the n forward input antennas, and a forward time delay section for delaying time from a signal from the forward signal processing section. And a combiner for combining the n forward signals outputted from the time delay unit.

In addition, as shown in FIG. 7, the reverse multiplex signal processor (Rx) 12 of the first embodiment of the present invention uses the same m as the input signal through a signal input to the reverse multiplex signal processor 12. And a reverse time delay section for time delaying the reverse signal from the split section, and a reverse signal processing section for processing signals from the reverse time delay section. The first reverse multiple signal processing unit 320 and the second reverse multiple signal processing unit 420 of the second embodiment of the present invention are respectively connected to the first reverse multiple signal processing unit and the second reverse multiple signal processing unit through a signal inputted thereto. A reverse time delay unit for dividing the signal into m signals equal to the input signal, and performing a time delay with respect to the reverse signal from the separation unit; It has an uplink signal processing unit for processing a signal from the unit time delay direction.

Here, every time delay used may be matched with a random number generator, for example, to randomly assign a time delay. Accordingly, it is common and preferable that the forward time delay units of the forward multiple signal processor, the first forward multiple signal processor, and the second forward multiple signal processor are each delayed by arbitrary time different from each other. In addition, it is generally preferable that the reverse time delay units of the reverse multiple signal processing unit, the first reverse multiple signal processing unit, and the second reverse multiple signal processing unit each generate a delay for a predetermined time different from each other.

In the following, the operation as applied to both the first embodiment and the second embodiment of the present invention will be described together.

As a method for achieving the above-mentioned object, the first problem to be solved is to combine multiple input signals using a multi-signal processing unit to accommodate the multi-antenna technology in the relay device. In order to accommodate the multi-antenna technology in the relay device, if the conventional method is to prepare a path for each input signal and separate the signal paths between the output port and the input port from each other, in the present invention, the input port is a signal of the multi-antenna technology. The number is the same but the output port is reduced to one, simplifying the internal structure of the relay. This can be implemented through the coupling part shown in FIG.

As described above, in combining signals through the coupling unit illustrated in FIG. 6, a delay is performed on a time axis when combining input signals in a manner of implementing a wireless channel environment required by a multi-antenna technique in a relay device. Combine the signals as if they had gone through multiple paths in a channel environment. If the signals are simply combined, they are not greatly affected by the transmit / receive diversity technique. However, the MIMO technique makes the wireless channel simple and difficult to achieve its original purpose. However, if the delay of each signal is different as in the present invention, it is possible to implement the characteristics of the MIMO technology by transmitting signals similar to the wireless channel environment. Similarly, even if applied to the transmit / receive diversity technology, when the multiple signal processor gives a time delay for each input signal and combines it, the signal is recognized by the signal processor of the base station or the terminal even though the signal is transmitted through a single path from the relay device. The original purpose of the transmit / receive diversity technology can be achieved.

Next, in order to accommodate the multiple antenna technology in the relay device, multiple output signals are separated using a multiple signal processor. Since the relay device must process not only the signal from the base station to the terminal, but also the signal from the terminal to the base station, when the multi-antenna technology is applied, the terminal receives the signal from the terminal through several antennas and prepares a path for each signal, thereby Should be delivered to. Such a method is a method of processing in a conventional relay device, and in the present invention, when receiving a signal of the terminal with one reverse input antenna and relaying it in one path and finally connecting to the base station, multiple signals, i.e. In the multiple antenna technology, as many signals as necessary are separated and connected to a base station. In this case, when the signal is separated in the multiple signal processor, a method of giving a time delay for each output signal is used. The reason for doing this is to maximize the effect of the multi-antenna technology by implementing the radio channel environment required by the transmit / receive diversity technology or the MIMO technology in the relay device as mentioned above.

In summary, in the multi-antenna technology, the number of antennas used in the base station and the terminal should prepare the input / output ports and paths in the relay device, but in the present invention, the downlink (forward) input ports connected to the base station are relayed by that number. It is provided in the device, and one down (forward) output port of the relay device is used, and the number of up (reverse) output ports connected to the base station is provided in the relay device, and input of the up (reverse) signal of the relay device. The port uses one. Of course, the down output port and the up input port of the repeater are combined into one by the front end unit of the repeater, and one antenna is used. In order to process the signal to which the multi-antenna technology is applied, each downlink signal and uplink signal are combined and separated in the multi-signal processing unit and pass through one path inside the repeater. Although it has passed through one path by giving a delay, different time delays are experienced. Therefore, the effect of passing through multiple paths is the core of the present invention.

The implementation of this repeater allows the multi-antenna technology to use transmit / receive diversity, MIMO signals, or both. However, there is an advantage that can be similar to the performance using a multi-antenna. In addition, since the internal structure of the repeater is simplified, there is an advantage of lowering the manufacturing cost. In particular, in the case of transmitting between the main hub unit (MHU) and the remote unit (RU) in the optical relay device or distributed relay device, the transmission amount can be significantly reduced.

As mentioned above, although this invention was demonstrated by the limited embodiment and drawing, this invention is not limited by this, The person of ordinary skill in the art to which this invention belongs, Various modifications, changes and variations are possible without departing from the scope of the claims to be described.

1 is a view schematically showing the structure of a repeater applying a multi-antenna technology (1Tx / 2Rx) in the existing repeater,

FIG. 2 is a diagram schematically illustrating a structure of a relay device to which a multi-antenna technique (2Tx / 2Rx) is applied to a conventional relay device.

FIG. 3 is a diagram schematically illustrating a structure of a relay device to which multiple antenna technologies (NTx / MRx) are applied in a conventional relay device.

4 is a diagram schematically showing a structure in which multiple antenna technology (NTx / MRx) is applied to a general relay device in the present invention.

FIG. 5 is a diagram schematically illustrating a structure in which a multi-antenna technique (NTx / MRx) is applied to a relay device composed of an MHU and an ROU in the present invention.

6 is a block diagram of a forward multiple signal processor Tx used in the present invention.

7 is a block diagram of a reverse multiple signal processor Rx used in the present invention.

<Explanation of symbols for the main parts of the drawings>

10 repeater

20 base stations

11 Forward Multiple Signal Processing Unit (Tx)

12 Reverse Multiple Signal Processing Unit (Rx)

13 Front End Unit (12)

14 One forward output antenna (ie, reverse input antenna)

100 repeater

200 base stations

300 Main Hub Unit (MHU)

310 first forward multiple signal processing unit

320 first reverse multiple signal processor

330 First Framer / Reframer

400 Remote Unit (RU)

410 second forward multiple signal processing unit

420 second reverse multiple signal processing unit

430 Second Framer / Reframer

440 Front End Unit (440)

500 one forward output antenna (ie reverse input antenna)

Claims (10)

delete delete delete delete delete delete N forward input antennas for receiving the forward signals of the base station; M reverse output antennas for transmitting reverse signals to the base station; A first forward multiple signal processor for processing the forward signal received from the forward input antenna and transmitting the processed forward signal to a framer / reframer, a first framer / reframer, and received from the first framer / reframer A main hub unit (MHU) including a first reverse multiple signal processor for processing one reverse signal and transmitting the reverse signal to the reverse output antenna; A second framer / reframer that exchanges a forward signal and a reverse signal with the first framer / reframer, a front end unit, and a forward signal received from the second framer / reframer to the front end unit. A remote unit comprising a second forward multiple signal processor for transmitting and a second reverse multiple signal processor for processing the reverse signal received from the front end unit and transmitting the signal to the second framer / reframer (RU); And And a forward output antenna which exchanges forward and reverse signals with the front end unit, transmits a forward signal to a terminal, and receives a reverse signal from the terminal, The first forward multiple signal processing unit and the second forward multiple signal processing unit, respectively, A separate forward signal processor for each of the n forward input antennas, and a forward time delay unit for delaying a signal from the forward signal processor; A coupling unit for coupling the n forward signals output from the forward time delay unit, The first reverse multiple signal processing unit and the second reverse multiple signal processing unit, respectively, A separation unit configured to separate the same signal into m signals through the signals inputted to the first reverse multiple signal processor and the second reverse multiple signal processor, A reverse time delay unit for time delaying the reverse signal from the separation unit, and a reverse signal processing unit for processing a signal from the reverse time delay unit, A relay apparatus using only max (m, n) antennas for the n forward input antennas and the m reverse output antennas. delete The method of claim 7, wherein Each of the forward time delay units of the first forward multiple signal processor and the second forward multiple signal processor is delayed by a predetermined time different from each other. The method of claim 7, wherein And the reverse time delay units of the first reverse multiple signal processor and the second reverse multiple signal processor are each delayed by an arbitrary time different from each other.

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