KR200433349Y1 - Apparatus for selecting RF signal path - Google Patents

Abstract

The present invention relates to a wireless communication signal transmission and reception path selection device, and comprises a receiver for performing signal processing of received information according to the present invention, a transmitter for transmitting predetermined information and a transmission or reception path between a plurality of transmit and receive antennas. The wireless communication signal transmission / reception path selecting apparatus selects at least one transmission antenna from among the plurality of common antennas and transmits the transmission information provided through the transmission unit through the transmission antenna. A transmission path selection unit configured to select at least one reception antenna among the plurality of antennas and to configure a reception path for providing reception information received through the reception antenna to the reception unit when receiving information; And a carrier transmitter configured to select at least one of the other antennas except for the reception antenna when receiving information, and configure a carrier path for transmitting carrier power provided through the transmitter. According to the present invention, the influence of the null can be minimized and the reception efficiency can be improved.

RFID, Transmit, Receive, Antenna, Tag, Circulator, SPDT, SP4T

Description

Apparatus for selecting RF signal path}

1 is a circuit diagram showing a conventional wireless communication signal transmission and reception path selection device,

2 is a graph showing the strength of carrier power over distance;

3 is a circuit diagram showing a wireless communication signal transmission and reception path selection apparatus according to an embodiment of the present invention,

4 is a circuit diagram showing a wireless communication signal transmission and reception path selection apparatus according to another embodiment of the present invention.

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

110: transmitter 115: coupler

120: signal branch unit 125: transmission and reception antenna selection unit

130: carrier antenna selector 140: receiver

145: transmission and reception antennas 150: operation switching unit

155: divider 160: power switching unit

170: amplification unit 180: transmission switching unit

The present invention relates to a wireless communication signal transmission and reception path selection device, and more particularly, to a wireless communication signal transmission and reception path selection device that can minimize the effect of null when receiving information in wireless communication and can increase the reception efficiency. It is about.

In general, a transmission / reception common antenna for both transmission and reception is used, and a transmission / reception system including a transmission unit and a reception unit requires an transmission path selection device for isolating the transmission unit and the reception unit and selecting a transmission path and a reception path.

The frequency division transmission / reception system, which is one of such transmission / reception systems, uses a duplexer to perform isolation between a transmitter and a receiver, thereby securing a transmission / reception path. In this case, it depends on the difference in the transmission and reception frequency, but in the duplexer (duplexer) it is possible to ensure sufficient isolation so that the transmission signal does not affect the receiver.

However, in the time division transmission and reception system, the same frequency is transmitted for a predetermined time and then received for a predetermined time. Therefore, the signal is separated from the transmitter and the receiver by using a signal branch circuit such as a circulator or the like, and then the receiver is blocked. It has secured a transmission and reception path by operating the method.

A transmission / reception path selection device in a transmission / reception system using such a circulator is shown in FIG. 1.

As shown in FIG. 1, the transmission / reception path selection device using a conventional circulator radiates a transmission signal TX of the transmission unit 10 through the transmission / reception common antennas 50, and radiates the antennas 50. In order to secure or select a transmission / reception path for transmitting a signal received through the reception unit 40, a circulator 20 and a single pole 4 throw (SP4T) switch 30 are provided.

The transmitter 10 generates and amplifies a transmission signal TX to be transmitted to the outside through the antennas 50 and outputs the amplified signal to the circulator 20. The transmitter 10 includes various filter (band filter, harmonic filter, etc.) circuits (not shown), a power amplifier 12, and the like.

The receiver 40 couples a received signal received through the circulator 20 and delays a phase by 90 °, various filters (band filter, variable filter, etc.) and a circuit (not shown). And a low noise amplifier (LNA) (not shown) for low noise amplifying a signal.

The circulator 20 is transmitted with little electrical loss of the signal supplied in the direction of the internal arrow, but is electrically isolated in the opposite direction of the arrow.

The circulator 20 receives the transmission signal TX output from the transmitter 10 through the first port 1 and outputs it to the second port 2. The signal output to the second port 2 is radiated through the transmission antenna ANT1 selected by the SP4T switch 30. When the signal A1 input through the reception antenna ANT1 is input to the second port 2, the signal A1 is output to the third port 3. The signal output to the third port 3 is input to the receiver 40.

The SP4T switch 30 is for selecting a transmission antenna for radiating a transmission signal output through the second port 2 of the circulator 20. In addition, the reception signal received through the reception antenna selected among the antennas 50 is to be input to the second port 2 of the circulator 20. The SP4T switch 30 is to be applied when the number of antennas is four. If the number of antennas is two, the SPDT switch may be used, and if the number of antennas is three, the SP3T switch may be used. The antenna selected by the SP4T switch 30 (for example, the first antenna ANT1) may also transmit and receive.

The antennas 50 use a transmit / receive antenna.

In the case of performing information transmission and information reception using the conventional transmission / reception path selection apparatus as described above, the antennas except for the selected antenna play no role and thus the efficiency thereof is low. In the case of the reception operation for receiving information from a tag when the transmission / reception path selection device is applied to an RFID system, carrier power must first be provided to the tag. In this case, the conventional transmit / receive path selection apparatus supplies the carrier power only through the reception antenna selected for reception.

However, when the tag is remote, there may be a case where the carrier power reaching the tag is insufficient to reach the threshold power for the tag to operate.

2 is a graph showing the strength of carrier power with distance. Here, the first graph (G1) is a graph showing the strength of the carrier power with respect to the distance in the ideal case, the second graph (G2) is a graph showing the strength of the carrier power with respect to the distance in the real environment. The third graph G3 shows the intensity of the threshold power which is the intensity of the minimum power for the tag to operate.

As shown in FIG. 2, when the tag maintains a distance of 10 m or less from the antenna, in the ideal case, since the carrier power is greater than or equal to the threshold power, the tag should operate normally. That is, the tag operates to transmit information to the antenna, and the antenna can receive information from the tag and operate normally. Here, the threshold power for tag operation is set to -17dBm, but generally -20dBm is regarded as the threshold power.

However, in a real environment, as in the circled portion 60 in the figure, a null occurs, and a case where the carrier power reaching the tag is considerably lower than the threshold power is generated so that information cannot be received from the tag. That is, even if the distance is less than 10m, the tag can not operate.

Accordingly, an object of the present invention is to provide a wireless communication signal transmission and reception path selection device that can overcome the above-mentioned conventional problems.

Another object of the present invention is to provide a wireless communication signal transmission and reception path selection device that can prevent or minimize the influence of the null.

Another object of the present invention is to provide a radio communication signal transmission and reception path selection device that can improve the reception efficiency.

Still another object of the present invention is to provide a wireless communication signal transmission / reception path selection device capable of transmitting and receiving information over a short distance as well as a long distance.

According to an embodiment of the present invention for achieving some of the above technical problems, a transmission unit for performing a signal processing of the reception information according to the present invention, and a transmission unit for transmitting a predetermined information and a plurality of transmission and reception antennas The wireless communication signal transmission / reception path selection device constituting the path selects at least one transmission antenna from the plurality of common antennas and transmits the transmission information provided through the transmission unit via the transmission antenna. A transmit / receive path selector configured to configure a transmit path for receiving the at least one receive antenna from the plurality of antennas and to provide the receive information received through the receive antenna to the receive unit when receiving information. Wow; And a carrier transmitter configured to select at least one of the other antennas except for the reception antenna when receiving information, and configure a carrier path for transmitting carrier power provided through the transmitter.

The carrier power is also transmitted through the reception antenna, and the transmission / reception path selection unit provides transmission information provided from the transmission unit to the transmission antenna when information is transmitted, and when the information is received, the reception is received through the reception antenna. A signal branch unit providing information to the receiver unit; A transmission / reception antenna selection unit may be provided to select the transmission antenna or the reception antenna from among the plurality of transmission / reception antennas when transmitting and receiving information.

The signal branch unit may include at least one of a 2-way divider, a coupler, and a circulator, and the transmit / receive antenna selector may include as many antennas as a single pole. Each switch having a row may be provided.

The carrier transmitter may include: a coupler for sampling a portion of carrier power provided through the transmitter; A divider for branching carrier power sampled through the coupler; A power switching unit for independently switching whether transmission of each carrier power branched through the divider; An amplifier having a plurality of amplifiers branched through the divider and amplifying respective carrier powers provided through the power switching unit; An antenna for transmitting the respective carrier powers provided through the amplifier may be selected, and a carrier antenna selector may be provided for selecting at least one or more antennas among the antennas other than the reception antenna among the plurality of antennas. . The carrier transmitter may further include an operation switching unit for controlling the overall operation of the carrier transmitter through switching between the coupler and the divider, or the carrier power output from each of the amplifiers to the carrier antenna selector. The apparatus may further include a transmission switching unit for controlling whether to transmit. The operation switching unit may include one SPDT switch, and the power switching unit and the transmission switching unit may each include as many SPDT switches as the number of antennas.

The wireless communication signal transmission / reception path selection device may configure an RFID reader together with the transmitter and the receiver, and the antennas may transmit and receive an RFID tag and an RF signal.

According to the above configuration, the influence by the null can be minimized and the reception efficiency can be improved.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings without any intention other than to provide a thorough understanding of the present invention to those skilled in the art.

3 is a circuit diagram showing a wireless communication signal transmission and reception path selection apparatus according to an embodiment of the present invention.

As shown in FIG. 3, a wireless communication signal transmission / reception path selection device according to an embodiment of the present invention is generally provided in a wireless communication system and performs a signal processing of a reception signal and transmits predetermined information. The apparatus for configuring a transmission or reception path between the transmitter 110 and the plurality of transmit / receive shared antennas 145.

The transmitter 110 generates, amplifies, and outputs a transmission signal Tx to be transmitted to the outside through the antennas 145. The transmitter 110 includes various filter (band filters, harmonic filters, etc.) circuits (not shown), power amplifiers, and the like.

The receiving unit 140 couples (receives) the received information (signal) received through the antennas 145 and at the same time delays by 90 °, various filters (band filter, variable filter, etc.) circuit (not shown) And a low noise amplifier (LNA) (not shown) for low noise amplifying the weak signal.

Wireless communication signal transmission and reception path selection device according to an embodiment of the present invention, the transmission and reception path selection unit 120, 125 and the carrier transmission unit (115, 155, 160, 170, 180, 130).

The transmission / reception path selection unit 120 or 125 selects at least one of the plurality of common antennas 145 as a transmission antenna when transmitting information. And a transmission path for wirelessly transmitting transmission information Tx provided through the transmission unit via the transmission antenna. In addition, at the time of receiving information, at least one of the plurality of antennas is selected as a reception antenna. In addition, a reception path for providing the reception information Rx received through the reception antenna to the reception unit 140 is configured.

The transmit / receive path selectors 120 and 125 include a signal branch unit 120 and a transmit / receive antenna selector 125.

The signal branch unit 120 provides the transmission information Tx provided from the transmission unit 110 to the transmission antenna when information is transmitted, and receives the reception information Rx received through the reception antenna when information is received. It is to provide to the receiving unit 140.

The signal branch unit 120 is generally a conventional regulator is used, but may be configured with at least one of a 2-way divider, a coupler, and a circulator. . For example, when the circulator is used, when the transmitting antenna and the receiving antenna are selected as the first antenna ANT1, the transmitting signal Tx output from the transmitting unit 110 is transferred to the first port 1. It receives and outputs it to the second port 2. The signal output to the second port 2 is radiated through the selected transmission antenna ANT1. When the reception signal A1 input through the reception antenna ANT1 is input to the second port 2, the reception signal A1 is output to the third port 3. The signal output to the third port 3 is input to the receiver 40 and subjected to a signal processing process.

The transmit / receive antenna selector 125 selects the transmit antenna or the receive antenna from the plurality of transmit / receive shared antennas 145 when transmitting and receiving information.

The transmit / receive antenna selector 125 may be configured to include switches each having as many throws as one antenna in a single pole. For example, when the number of antennas is four, the transmission / reception antenna selector 125 may include an SP4T switch. The transmit / receive antenna selector 125 may select an antenna having the best transmission sensitivity as a transmission antenna or select an arbitrary antenna as a transmission antenna when transmitting information. When receiving information, it is received through an antenna selected as a transmission antenna and doubles transmission and reception.

The carrier transmitters 115, 155, 160, 170, 180, and 130 select at least one or more antennas other than the reception antennas selected by the transceiver antenna selector 125 when receiving information, and provide the information through the transmitter 110 for information reception. Configure a carrier path for transmitting the carrier power through the selected antenna. For example, in the case of four antennas and one of them is selected as a transmit / receive antenna, at least one of the remaining three antennas is selected to transmit or radiate carrier power. All three antennas may be selected or only some of them may be selected.

Of course, carrier power may also be transmitted through the selected transmission / reception antenna. This is possible through the transmission path at the time of information transmission.

The carrier transmitters 115, 150, 155, 160, 170, and 130 include a coupler 115, a divider 155, a power switching unit 160, an amplifier 170, a transmission switcher 180, and a carrier antenna selector 130.

The coupler 115 may branch some of the carrier power provided through the transmitter 110, and replace the coupler 115 with a divider. The coupler 115 may be connected between the transmitter 110, the signal branch 120, and the divider 155. In this case, the coupler 115 may use a -10dBm coupler. That is, when carrier power of 30 dBm is supplied from the transmitter 110, the signal branch unit 120 is supplied with carrier power of approximately 30 dBm, and the divider 155 is supplied with carrier power of 20 dBm. do.

The divider 155 branches the carrier power branched through the coupler 115 by the number of antennas 145. For example, a four-way divider may be used when four transmit / receive shared antennas ANT1, ANT2, ANT3, and ANT4 are used. When the carrier power of 20 dBm is supplied to the divider 155 and a 4-way divider is used, each branched carrier power may be about 14 dBm attenuated by 6 dB.

The power switching unit 160 independently switches the transmission of each carrier power branched through the divider 155. For example, if the carrier power should be transmitted through the carrier path connected to the selected receiving antenna, the carrier power is blocked. If the carrier power is transmitted through the carrier path connected to the remaining antennas, the carrier power is not blocked.

The power switching unit 160 may be configured to include as many SPDT switches 162, 164, 166, and 168 as the number of antennas 145. Each of the SPDT switches 162, 164, 166, and 168 is connected to an output line of the divider 155, respectively. When the divider 155 is a 4-way divider, each of the four output lines of the divider 155 and the SPDT switches 162, 164, 166, and 168 are connected to each other.

Accordingly, when the reception antenna is selected as the first antenna ANT1, the SPDT switch 162 in which the carrier path is formed with the reception antenna ANT1 among the switches 162, 164, 166 and 168 constituting the power switching unit 160 is formed. Open and the remaining switches 164, 166, 168 are closed. If only some of the remaining antennas ANT2, ANT3, and ANT4 are selected as carrier antennas, only the switches configured by the antenna selected as the carrier antenna and the carrier path may be closed and the remaining switches may be opened.

The amplifying unit 170 is for amplifying each carrier power branched through the divider 155 and provided through the power switching unit 160. The amplifier 170 includes as many amplifiers 172, 174, 176, and 178 as the number of antennas 145. The amplifiers 172, 174, 176, and 178 are connected to the respective switches 162, 164, 166, and 168 constituting the power switching unit 160 to amplify carrier power provided through the power switching unit 160. For example, the carrier power provided at a level of about 14 dBm is amplified to have a level of 30 dBm, which is the same level as that provided by the transmitter 110. Of course, the switch constituting the power switching unit 160 is open and does not operate when carrier power is not supplied.

The transmission switching unit 180 is for controlling whether to transmit the carrier power output from each of the amplifiers 172, 174, 176, and 178. The transmission switching unit 180 has the same configuration as the power switching unit 160. That is, it may be configured to include as many SPDT switches 182, 184, 186, 188 as the number of antennas 145. Accordingly, when the reception antenna is selected as the first antenna ANT1, the SPDT switch 182 in which the carrier path is formed with the reception antenna ANT1 among the switches 182, 184, 186 and 188 constituting the transmission switching unit 180 is Open and the remaining switches 184, 186, 188 are closed. When only some of the remaining antennas ANT2, ANT3, and ANT4 are selected as carrier antennas, only the switches configured by the antenna selected as the carrier antenna and the carrier path may be closed and the Namoji switches may have an open operation.

The transmission switching unit 180 and the power switching unit 160 are to secure sufficient isolation, and may be constituted by only one switching unit if sufficient isolation is secured through any one switching unit.

The carrier antenna selector 130 selects a carrier antenna for transmitting respective carrier powers provided through the amplifier 170 or the transmission switching unit 180. At least one antenna among the antennas other than the reception antenna is selected from among the plurality of antennas.

In addition, when the carrier antenna selector 130 is connected between the transmit / receive antenna selector 125 and the antennas 145, when a transmit or receive antenna is selected by the transmit / receive antenna selector 125, the carrier antenna selector 130 is selected in association with the carrier antenna selector 130. Switching between the antenna and the transmit / receive antenna selector 125 is performed. For efficiency, the carrier antenna selector 130 may switch between the antennas 145 and the transmit / receive antenna selector 125 or the transmit switcher 180.

The carrier antenna selector 130 includes as many SPDT switches 132, 134, 136, and 138 as the number of the antennas 145, so that each of the switches 132, 134, 136, 138, the amplifiers 172, 174, 176, 178, or the transmission switches 182, 184, 186, 188. It can be configured in connection with each.

When the transmit or receive antenna is selected as the first antenna ANT1 through the carrier antenna selector 130 and the transmit / receive antenna selector 125, the first antenna ANT1 and the transmit / receive antenna selector ( Switching of the switches 132 for connecting 125 to each other is performed. Then, switching is performed to select a carrier antenna among the remaining antennas ANT2, ANT3, and ANT4 except the selected receiving antenna ANT1 through the remaining switches 134, 136, and 138.

The operation of the wireless communication signal transmission / reception path selection device according to an embodiment of the present invention having the configuration as described above will be briefly described.

First, the operation at the time of information transmission is as follows.

The transmission information Tx provided from the transmitter 110 is input through the first port 1 of the signal branch unit 120 and output through the second port 2. Thereafter, the transmission information Tx is radiated or transmitted through the transmission antenna (first antenna ANT1) selected through the transmission / reception antenna selection unit 125.

In this case, all the switches constituting the power switching unit 160 and the transmission switching unit 180 remain open. The switch 132 connected to the transmission antenna ANT1 selected from the switches 132, 134, 136, and 138 constituting the carrier antenna selection unit 130 may include the transmission / reception antenna selection unit 125 and the first antenna ANT1 which is the transmission antenna. ) Is switched in the direction of connecting each other.

Next, the operation upon receiving information is as follows.

First, it is assumed that the receiving antenna is selected as the first antenna ANT1 in the same manner as the transmitting antenna. The reception information A1 received through the reception antenna is input to the second port 2 of the signal branch unit 120 through the transmission / reception antenna selection unit 125. The reception information input to the second port 2 of the signal branch unit 120 is output through the third port 3 of the signal branch unit 120 and is input to the receiver 140. Prior to receiving the received information, an operation for transmitting carrier power to the tag is preceded. At the same time, the carrier transmitter operates. That is, among the switches 162, 164, 166, 168, 182, 184, 186 and 188 of the switches 162, 164, 166, 168, 182, 184 and 186, which constitute the power switching unit 160 and the transmission switch unit 180, the switches 162 and 182 formed with a path are opened, and the remaining switches 164, 166, 168, 184, 186 and 188 are closed. do. That is, the switches 162 and 182 formed with a path to the receiving antenna ANT1 are connected to ground, and the remaining switches 164, 166, 168, 184, 186 and 188 are amplified by the amplifier 170, the divider 155, and the carrier antenna to form a carrier path. It is closed to connect the selector 130 to each other. Of course, when only some antennas are selected for the carrier power transmission, the power switching unit 160 and the transmission switching unit 180 operate to form a carrier path corresponding thereto.

The switch 132 connected to the transmission antenna ANT1 selected from the switches 132, 134, 136, and 138 constituting the carrier antenna selection unit 130 may include the transmission / reception antenna selection unit 125 and the first antenna ANT1. ) Is switched in the direction of connecting each other. The remaining switches 134, 136, and 138 of the carrier antenna selector 130 perform switching to select at least one or more of the antennas ANT2, ANT3, and ANT4 excluding the receiving antenna as a carrier antenna.

4 is a circuit diagram showing a wireless communication signal transmission and reception path selection apparatus according to another embodiment of the present invention. FIG. 4 is a simplified version of FIG. 3 except for some components.

As shown in FIG. 4, a wireless communication signal transmission / reception path selection device according to another embodiment of the present invention is generally provided in a wireless communication system and performs a signal processing of a received signal and transmits predetermined information. The apparatus for configuring a transmission or reception path between the transmitter 110 and the plurality of transmit / receive shared antennas 145.

The transmitter 110 generates, amplifies, and outputs a transmission signal Tx to be transmitted to the outside through the antennas 145. The transmitter 110 includes various filter (band filter, harmonic filter, etc.) circuits (not shown), power amplifiers, and the like.

The receiving unit 140 couples (receives) the received information (signal) received through the antennas 145 and at the same time delays by 90 °, various filters (band filter, variable filter, etc.) circuit (not shown) And a low noise amplifier (LNA) (not shown) for low noise amplifying the weak signal.

Wireless communication signal transmission and reception path selection device according to an embodiment of the present invention, the transmission and reception path selection unit 120, 125 and the carrier transmission unit (115, 155, 160, 170, 130).

The transmission / reception path selection units 120 and 125 are the same as described with reference to FIG. 3.

The carrier transmitters 115, 150, 155, 160, 170, and 130 select at least one or more antennas other than the reception antennas selected by the transceiver antenna selector 125 when receiving information, and provide the information through the transmitter 110 for information reception. Configure a carrier path for transmitting the carrier power through the selected antenna. For example, when four antennas and one of the antennas are selected as receiving antennas, at least one of the remaining three antennas is selected to transmit or radiate carrier power. All three antennas may be selected or only some of them may be selected.

Of course, carrier power may also be transmitted through the selected receiving antenna. This is possible through the transmission path at the time of information transmission.

The carrier transmitters 115, 150, 155, 160, 170, and 130 include a coupler 115, an operation switcher 150, a divider 155, a power switcher 160, an amplifier 170, and a carrier antenna selector 130. The carrier transmitters 115, 150, 155, 160, 170, and 130 are further provided with an operation switching unit 150, unlike the embodiment of the present invention, and the transmission switching unit 180 is not provided.

The coupler 115 is the same as in FIG.

The operation switching unit 150 is for controlling the overall operation of the carrier transmission unit by switching between the coupler 115 and the divider 155. That is, switching is performed to operate only when the information is turned off and the carrier power is transmitted. The operation switching unit 150 may include an SPDT switch.

The divider 155 receives carrier power sampled through the coupler 115 through the operation switching unit 150 and branches the number of antennas 145. For example, a four-way divider may be used when four transmit / receive shared antennas ANT1, ANT2, ANT3, and ANT4 are used. When the carrier power of 20 dBm is supplied to the divider 155 and a 4-way divider is used, each branched carrier power may be about 14 dBm attenuated by 6 dB.

The power switching unit 160 independently switches the transmission of each carrier power branched through the divider 155. For example, if the carrier power should be transmitted through the carrier path connected to the selected receiving antenna, the carrier power is blocked. If the carrier power is transmitted through the carrier path connected to the remaining antennas, the carrier power is not blocked.

Since the operation of the power switching unit 160 and the amplifying unit 170 is the same as in FIG. 3, a description thereof will be omitted.

The carrier antenna selector 130 selects a carrier antenna for transmitting respective carrier powers provided through the amplifier 170. At least one of the antennas other than the reception antenna is selected from among the plurality of antennas. Since the operation and configuration of the carrier antenna selector 130 are the same as those described with reference to FIG. 3, the description thereof will be omitted.

Operation of the wireless communication signal transmission and reception path selection device according to another embodiment of the present invention having the configuration as described above will be briefly described.

First, the operation at the time of information transmission is as follows.

The transmission information Tx provided from the transmitter 110 is input through the first port 1 of the signal branch unit 120 and output through the second port 2. Thereafter, the transmission information Tx is radiated or transmitted through the transmission antenna (first antenna ANT1) selected through the transmission / reception antenna selection unit 125.

In this case, all the switches constituting the operation switching unit 150 and the power switching unit 160 remain open (or off). The switch 132 connected to the transmission antenna ANT1 selected from the switches 132, 134, 136, and 138 constituting the carrier antenna selection unit 130 may include the transmission / reception antenna selection unit 125 and the first antenna ANT1 which is the transmission antenna. ) Is switched in the direction of connecting each other.

Next, the operation upon receiving information is as follows.

First, it is assumed that the receiving antenna is selected as the first antenna ANT1 in the same manner as the transmitting antenna. The reception information A1 received through the reception antenna is input to the second port 2 of the signal branch unit 120 through the transmission / reception antenna selection unit 125. The reception information input to the second port 2 of the signal branch unit 120 is output through the third port 3 of the signal branch unit 120 and is input to the receiver 140. Prior to receiving the received information, an operation for transmitting carrier power to the tag is preceded. The carrier transmitter operates for this purpose. That is, the switch of the operation switching unit 150 is closed or on, and a switch in which a path is formed with the reception antenna ANT1 among the switches 162, 164, 166, and 168 constituting the power switching unit 160. 162 is open and the remaining switches 164, 166, 168 are closed. That is, the switches 162 formed with a path to the receiving antenna ANT1 are connected to ground, and the remaining switches 164, 166, and 168 are the amplifying unit 170, the divider 155, and the carrier antenna to form a carrier path. It is closed to connect the selector 130 to each other. Of course, when only some antennas are selected for the carrier power transmission, the power switching unit 160 operates to form a carrier path corresponding thereto.

The switch 132 connected to the transmission antenna ANT1 selected from the switches 132, 134, 136, and 138 constituting the carrier antenna selection unit 130 may include the transmission / reception antenna selection unit 125 and the first antenna ANT1. ) Is switched in the direction of connecting each other. The remaining switches 134, 136, and 138 of the carrier antenna selector 130 perform switching to select at least one or more of the antennas ANT2, ANT3, and ANT4 excluding the receiving antenna as a carrier antenna.

An embodiment of the present invention described with reference to FIG. 3 may secure sufficient isolation than other embodiments of the present invention described with reference to FIG. 4. That is, when the switches are not sufficiently secured, in the case of FIG. 3, which is an embodiment of the present invention, sufficient isolation is secured because the switching is performed through the power switching unit 160 and the transmission switching unit 180. 4, which is another embodiment of the present invention, since sufficient switching is performed only through the power switching unit 160, sufficient isolation may not be secured. However, another embodiment of the present invention described in FIG. 4 has the advantage that the circuit is simple and easy to control than the embodiment of the present invention described in FIG. 3.

The radio communication signal transmission / reception path selection device having the structure described above may be applied to a radio frequency identification (RFID) system. The RFID system may include an RFID tag, an RFID reader, a server, or a network. The tag storing the product information is attached to the product, and the antenna attached to the tag transmits this information wirelessly to several meters to several tens of meters, and the reader receives this signal, decodes the product information, and transmits it to the server. When the apparatus for transmitting / receiving a wireless communication signal transmission / reception path according to an embodiment of the present invention is applied to the RFID system, the transmitter, the receiving unit, and the antennas may be part of the RFID reader, including the apparatus for transmitting / receiving a wireless communication signal transmission / reception path. Can be. The operation of other RFID system is well known to those skilled in the art to which the present invention pertains, and a description thereof will be omitted.

As described above, by configuring the wireless communication signal path transmission and reception path selection apparatus according to the embodiments of the present invention, it is possible to increase the level of carrier power reaching the tag. That is, the antennas are installed at different positions, and information reception is facilitated when a power transmitting antenna that transmits only a carrier and not a selected transmitting / receiving antenna is located near a tag to receive information. That is, when the power of a carrier reaching the tag because the distance from the selected transmit / receive antenna is far from the tag is transmitted to the tag or is affected by null, the carrier power may be received from another antenna nearby. The reception efficiency can be improved.

In addition, in RF communication, as the distance increases, the probability of occurrence of null is high and the probability of lowering the carrier power below the threshold power increases. However, in the present invention, since the carrier power is provided from several antennas, it is possible to reduce the probability of occurrence of null in the place where the tag is located or the probability of the carrier power being lowered below the threshold power.

In addition, since the carrier power can be provided from several antennas, the absolute power reaching the tag may be high, thereby enabling transmission and reception of data (information) at a far distance from the conventional art.

Since the description of the above embodiment is merely an example with reference to the drawings for a more thorough understanding of the present invention, it should not be construed as limiting the present invention. In addition, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the basic principles of the present invention. For example, it is clear that in other cases, the internal configuration of the circuit may be changed or the internal components of the circuit may be replaced with other equivalent elements.

As described above, according to the present invention, the antennas are installed at different positions, and when an antenna other than the selected transmit / receive antenna is located near a tag that is to receive information, the level of carrier power reaching the tag is determined. It is possible to increase the reception efficiency. That is, when the carrier power is transmitted below the threshold power of the tag because the distance from the selected transmit / receive antenna is far away, or when it is affected by null, the carrier power can be received from another nearby antenna, thereby increasing reception efficiency. have. In addition, since the carrier power is provided from several antennas, it is possible to reduce the probability of occurrence of null in the place where the tag is located or the probability that the carrier power is lowered below the threshold power. In addition, since carrier power may be provided from several antennas, the absolute power reaching the tag may be high, and thus data may be transmitted and received at a far distance from the prior art.

Claims (10)

A wireless communication signal transmission / reception path selection apparatus for configuring a transmission or reception path between a reception unit performing signal processing of reception information, a transmission unit for transmitting predetermined information, and a plurality of transmission / reception common antennas: When transmitting information, at least one transmission antenna of the plurality of common antennas is selected, and through the transmission antennas, a transmission path for wireless transmission of transmission information provided through the transmission unit is configured. A transmission / reception path selection unit configured to select at least one reception antenna from among antennas and to configure a reception path for providing reception information received through the reception antenna to the reception unit; And a carrier transmitter configured to select at least one or more antennas other than the reception antenna when receiving information, and configure a carrier path for transmitting carrier power provided through the transmitter. Transmission path selector. The method of claim 1, And the carrier power is also transmitted through the reception antenna. The method of claim 1, wherein the transmission and reception path selection unit, A signal branch unit which provides transmission information provided from the transmission unit to the transmission antenna when transmitting information, and provides reception information received through the reception antenna to the reception unit when receiving information; And a transmission / reception antenna selection unit for selecting the transmission antenna or the reception antenna from among the plurality of transmission / reception common antennas during information transmission / reception. The method of claim 3, wherein the signal branch unit, And a at least one of a 2-way divider, a coupler, and a circulator. The method according to claim 3 or 4, The transmit / receive antenna selector includes a switch having a single number of throws in a single pole, and the transmit / receive antenna selector includes an SP4T switch when the number of antennas is four. Wireless communication signal transmission and reception path selection device characterized in that. The method of claim 1. The carrier transmission unit, A coupler for branching some of the carrier power provided through the transmitter; A divider for branching carrier power sampled through the coupler; A power switching unit for independently switching whether transmission of each carrier power branched through the divider; An amplifier having a plurality of amplifiers branched through the divider and amplifying respective carrier powers provided through the power switching unit; Selecting an antenna for transmitting the respective carrier powers provided through the amplifier, characterized in that it comprises a carrier antenna selection unit for selecting at least one or more of the remaining antennas other than the receiving antenna of the plurality of antennas Wireless communication signal transmission and reception path selection device. The method of claim 6. The carrier transmission unit, And an operation switching unit for controlling the overall operation of the carrier transmitter through switching between the coupler and the divider. The method of claim 6. The carrier transmission unit, And a transmission switching unit for controlling whether to transmit the carrier power output from each of the amplifiers to the carrier antenna selection unit. The method of claim 7 or 8. And the operation switching unit includes one SPDT switch, and the power switching unit and the transmission switching unit each include as many SPDT switches as the number of antennas. According to claim 1, wherein the wireless communication signal transmission and reception path selection device And an RFID reader together with the transmitter and the receiver, wherein the antennas transmit and receive an RFID tag and an RF signal.

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