KR20100038736A - Transceiver for time division duplex and method for switching thereof - Google Patents

Abstract

PURPOSE: A transmission of a TDD mode and a transceiving switching method thereof for a bidirectional wireless communication of a microwave and RF signals are provided to perform high-power signal process by using low-priced switching element by processing transceiving switching. CONSTITUTION: A power amplifier(130) amplifies microwave and the transmitted high frequency signals. An LNA(Low Noise Amplifier)(140) amplifies and controls low noise of high frequency signals and the received microwave. If the power amplifier is connected, a first switch switches in order to operate the power amplifier. If the low amplifier is connected, a second switch switches in order to operate the lower power amplifier.

Description

Transmitting and receiving switching method of a time division duplex method and its transmission and reception method {TRANSCEIVER FOR TIME DIVISION DUPLEX AND METHOD FOR SWITCHING THEREOF}

The present invention relates to a bidirectional communication system, and more particularly, to a time division duplex (TDD) transmission and reception apparatus and a transmission and reception switching method thereof capable of large capacity transmission using high speed switching.

In general, microwave and high-frequency wireless communication systems use a variety of communication methods, such as frequency division duplex (FDD) and time division duplex (TDD) for bidirectional wireless communication. The FDD method is a method of transmitting and receiving data using different frequencies by allocating a frequency domain at the time of transmission and a frequency domain at the reception, and the TDD method is a method of transmitting and receiving data by temporal distribution using the same frequency.

In the field of broadcasting and communication where high speed data communication is increasingly required, in order to transmit a large amount of data, the FDD scheme has a disadvantage in that the frequency efficiency is low because the amount of data to be transmitted and the frequency band have a proportional relationship with each other. This encourages the high cost of microwave and high frequency wireless communication systems. That is, in the case of microwave and high frequency, since most devices and modules are expensive, there are many obstacles in the system configuration.

 In contrast, the TDD scheme using the same frequency maximizes frequency efficiency and eliminates the need for a high performance duplexer required by the FDD scheme. However, technically, a technique for protecting a low noise amplifier (LNA) of a receiver during transmission and a technique for minimizing noise inflow of a transmitter during reception are required. For example, a power amplifier (PA) of a transmitter may amplify noise even when only power is applied.

Referring to FIG. 1, a general time division duplex (TDD) transmission and reception apparatus 10 includes a transmitter 30 for transmitting data using one antenna 12 and a receiver 40 for receiving data. . In addition, the transceiver 10 includes a first switch 16 provided at an input terminal 14 for inputting TDD-type microwave and radio frequency (RF) signals, and an output terminal, that is, an antenna 12 side. A second switch 18 included in the control unit, a local oscillator 20 generating a reference frequency signal, and a third switch 22 switching to output the reference frequency signal to the transmitter 30 or the receiver 40. do. The transceiver 10 is provided as one module and is used in a bidirectional wireless communication system capable of transmitting data at the same frequency.

In detail, the transmitter 30 is provided between the first and second switches 16 and 18, and the microwave / RF signal input from the first switch 16 and the reference frequency signal from the third switch 22. First mixer 32 for receiving and synthesizing a signal, and a power amplifier (PA) 34 for amplifying a microwave / RF signal output from the first mixer 32 and outputting it to the second switch 18. ).

The receiver 40 is disposed in parallel with the transmitter 30 and is provided between the first and second switches 16 and 18, and the microwave is input from the antenna 12 via the second switch 18. A low noise amplifier (LNA) 44 which removes and amplifies the noise of the signal, and a second mixer for receiving and combining the output signal of the low noise amplifier 44 and the reference frequency signal from the local oscillator 20 ( 42).

Therefore, the transmission and reception apparatus 10 simultaneously transmits or receives the first to third switches 16, 18, and 22 when transmitting and receiving data in the TDD scheme. That is, during data transmission, the first to third switches 16, 18 and 22 are switched to connect to the transmitter 30, and when the data is received, the first to third switches 16, 18 and 22 are connected to the receiver ( Switch to 40).

In general, transceivers require high power amplifiers for microwave and RF for long distance wireless communications, large capacity and high speed data transmission. However, in the case of the high output, the transceiver 10 has to switch the signal of the second output 18 which is also installed at the output stage, and also the high output. The high output switching element is very expensive and the insertion loss is large due to the use of the high power amplifier. As a result, the application of high power amplifiers is difficult.

In addition, the transmission and reception apparatus 10 should have no signal interference between the transmitter 30 and the receiver 40. When a high power amplifier is used, there is a problem in that isolation is not secured during transmission and reception.

An object of the present invention is to provide a time division duplex transmission and reception apparatus capable of high-speed switching and a switching method thereof.

Another object of the present invention is to provide a time division duplex transmission and reception apparatus and a switching method thereof for minimizing noise inflow of a transmitting end and simultaneously protecting a receiving end.

It is still another object of the present invention to provide a time division duplex transmission and reception apparatus and a switching method thereof for high capacity data transmission.

It is still another object of the present invention to provide a time division duplex transceiver apparatus and a switching method thereof for high speed data transmission.

It is still another object of the present invention to provide a time division duplex transceiver apparatus and a switching method thereof for using a high output power amplifier.

It is still another object of the present invention to provide a time division duplex transmission and reception apparatus and a switching method thereof to reduce manufacturing cost.

Another object of the present invention is to isolate when transmitting and receiving using a high-power power amplifier

The present invention provides a time division duplex transmission and reception apparatus and a switching method thereof.

To achieve the above objects, the time division duplex transmission / reception device of the present invention is characterized by using a low-cost switching device. In this way, the transceiver can be switched at high speed.

A time division duplex transmission / reception apparatus according to the present invention includes a power amplifier configured to transmit a microwave and a high frequency signal of a time division duplex method to an antenna and amplify the microwave and high frequency signals to be transmitted; A low noise amplifier provided in the receiving unit for receiving the time division duplex type microwave and high frequency signals from the antenna, and suppressing and amplifying low noise of the received microwave and high frequency signals; A first switch coupled to the power amplifier and switching to drive the power amplifier upon transmission; And a second switch connected to the low noise amplifier and switching to receive the low noise amplifier upon reception.

In one embodiment, the transceiver device; A third switch provided at an input end and switching to select the transmitter or the receiver; A circulator provided on the antenna side and operative to select the transmitter or the receiver; In transmission, the first and the third switch are simultaneously switched so that the transmitter is activated, and when receiving, the second and the third switch are simultaneously switched so that the receiver is activated.

In another embodiment, the power amplifier includes a first field effect transistor; The first switch is connected to the drain terminal of the first field effect transistor.

In another embodiment, the transceiver device; A first bypass circuit is further provided between the first switch and the first field effect transistor.

In another embodiment, the first field effect transistor; A bias terminal connected to the gate terminal to bias the voltage is provided, and a second bypass circuit is provided between the bias terminal and the gate terminal.

In yet another embodiment, the low noise amplifier comprises a second field effect transistor; The second switch is connected to the drain terminal of the second field effect transistor.

In another embodiment, the transceiver device; A third bypass circuit is further provided between the second switch and the second field effect transistor.

In another embodiment, a first impedance converter is further provided between the drain terminal of the first field effect transistor and the first bypass circuit.

In another embodiment, a second impedance converter is further provided between the drain terminal of the second field effect transistor and the third bypass circuit.

In another embodiment, the transceiver device; Electrically connected to the first to third switches to turn on the first switch, turn off the second switch, and turn off the third switch in response to microwave and high frequency signals in a time division duplex manner. And a controller configured to control switching to be connected to a transmitter, to turn on the second switch, to turn off the first switch, and to control the third switch to be connected to the receiver.

According to another feature of the present invention, there is provided a fast switching method for transmitting and receiving switching of a time division duplex transmission and reception apparatus. The transceiver includes a first switch connected to a power amplifier provided in a transmitter, a second switch connected to a low noise amplifier of a receiver, a third switch switched to be connected to a transmitter or a receiver, and a circulator connected to an antenna. Include.

According to this method, switching is controlled so that the third switch is connected to the transmitting unit during transmission. Simultaneously turn on the first switch and turn off the second switch. In response to the reception, the third switch is controlled to be connected to the receiver. At the same time, the second switch is turned on and the first switch is turned off to process data transmission.

In one embodiment, the transmission and reception switching method; When the first switch is on, the power amplifier is operated. When the second switch is on, the low noise amplifier is operated.

As described above, the time division duplex transmission and reception apparatus of the present invention can be switched at high speed to switch between transmission and reception using a high output low cost switching element, thereby minimizing noise inflow at the transmitting end and simultaneously protecting the receiving end.

In addition, the transmission and reception apparatus of the present invention can secure isolation when transmitting and receiving using a high output power amplifier.

In addition, the transceiver of the present invention can reduce the manufacturing cost of the wireless communication system by using a low-cost switching element.

In addition, the transmission and reception apparatus of the present invention enables high-capacity data transmission in a time division duplex method with high-speed switching, and may use a high power power amplifier.

The embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be interpreted as being limited by the embodiments described below. This embodiment is provided to more completely explain the present invention to those skilled in the art. Therefore, the shapes and the like of the components in the drawings are exaggerated in order to emphasize a clearer explanation.

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 2 to 9.

2 is a block diagram showing a schematic configuration of a bidirectional wireless communication system using a time division duplex transceiver according to the present invention.

Referring to FIG. 2, the wireless communication system 2 includes, for example, a plurality of servers 4 and 8 and a server 4 to transmit high capacity data such as an image at high speed (about 18 GB). 8) a repeater 6 for relaying data between them.

The servers 4 and 8 each have a time division duplex transceiver 100 according to the present invention, and are mutually wireless in a one-to-many manner with a plurality of clients (not shown) equipped with the same transceiver 100. Handle the communication. The repeater 6 includes a plurality of transmitting and receiving devices 100 corresponding to the servers 4 and 8 to enable wireless communication with the servers 4 and 8 in a one-to-one manner. Of course, the repeater 6 may include one transmitting and receiving device 100, and a plurality of repeaters 6 may be provided corresponding to the servers 4 and 8.

The transmission and reception apparatus 100 of the present invention is disposed in the servers 4 and 8, the repeater 6 and the clients so that the antennas face each other by the straightness of the microwave and the high frequency signals.

The transmission and reception apparatus 100 of the present invention is capable of high-speed switching, signal isolation, and high-speed large-capacity data processing by using a low-cost switching element for high power.

The transmission and reception apparatus of the present invention will be described in detail with reference to FIGS. 3 to 9.

3 is a block diagram showing the configuration of a transmitting and receiving device according to the present invention, Figures 4 and 5 are circuit diagrams showing the configuration of the first and second switches.

Referring to FIG. 3, the transceiver 100 includes a power amplifier 130 provided in the transmitter 160, a low noise amplifier 140 provided in the receiver 170, and a first amplifier connected to the power amplifier 130. A switch 120, a second switch 122 connected to the low noise amplifier 140, and a controller 106 for controlling overall operations of the transceiver 100. In addition, the transmission and reception apparatus 100 is connected to various applications 104 according to the functions of the wireless communication system 2, and the third switch 110 is installed on the input terminal side to receive microwave and high frequency signals from the application 104 ) And a circulator 118 provided on the antenna 102 side. For example, the application 104 includes an access point (AP), a modem (MODEM), a mesh (mesh), etc., depending on the servers 4, 8, the repeater 6, a client (not shown), and the like.

In addition, the transceiver 100 includes a local oscillator 108 for generating a reference frequency signal, and a fourth switch 112 for switching to provide the reference frequency signal to the transmitter 160 or the receiver 170. In addition, although the transmission and reception apparatus 100 is not shown in the drawing, at least one bandpass filter is installed between each component. The transceiver 100 may be provided with each component individually or may be provided as one communication module including each component.

The transmitter 160 may include a first variable attenuator 114 that adjusts gains of microwave and high frequency signals input from the application 104, and a first mixer that synthesizes gain-adjusted microwave and high frequency signals and a reference frequency signal. 124 and a power amplifier 130 that amplifies the synthesized microwave and high frequency signals.

The receiver 170 includes a low noise amplifier 140 for suppressing and amplifying noise of microwave and high frequency signals input from the antenna 102, a second mixer for synthesizing the amplified microwave and high frequency signals and a reference frequency signal ( 126 and a second variable attenuator 116 that adjusts the gain of the synthesized microwave and high frequency signals to the application 104. The transmitter 160 and the receiver 170 are disposed in parallel to each other between the third switch 110 and the circulator 118.

The circulator 118 has three asymmetric terminals and passes microwave and high frequency signals in only one direction. That is, during transmission or reception, microwave and high frequency signals are transmitted to adjacent terminals in the direction of the arrow.

The controller 106 outputs the switching control signals CTL and CTL # to switch the first to third switches 120, 122, and 110 in response to the transmitted TDD signal.

Specifically, referring to FIG. 4, the first switch 120 is connected to the power amplifier 130. The first switch 120 and the power amplifier 130 may be provided as one device.

The power amplifier 130 includes a first field effect transistor for power amplification between an input terminal IN for inputting microwave and high frequency signals and an output terminal OUT for outputting amplified microwave and high frequency signals. Transistor: Power FET) 132. The first field effect transistor 132 is provided with an N-channel MOSFET.

That is, in the power amplifier 130, an input terminal IN is connected to a gate terminal of the first field effect transistor 132, and an output terminal OUT is a drain of the first field effect transistor 132. ) Is connected to the terminal. The power amplifier 130 also includes blocking capacitors C5 and C6 between the input terminal IN and the gate terminal, and between the drain terminal and the output terminal OUT.

The power amplifier 130 applies a bias voltage to the gate terminal of the first field effect transistor 132. To this end, a first bypass circuit 150 and a first impedance converter 134 are installed in series between the terminal V _bais to which the bias voltage is applied and the gate terminal. The power amplifier 130 is provided with a first switch 120 between the drain terminal of the first field effect transistor 132 and the terminal V _D for applying the drain voltage. In the power amplifier 130, a second bypass circuit 152 and a second impedance converter 136 are provided in series between the first switch 120 and the drain terminal. Here, the first and second bypass circuits 150 and 152 are each provided with noise canceling capacitors C1 to C2 and C3 to C4, and the first and second impedance converters 134 and 136 are respectively lambda / It is provided with four transmission lines.

Therefore, when the power amplifier 130 receives the switching control signal CTL from the controller 106 at the time of transmission and the first switch 120 is turned on, the drain voltage and the bias voltage become the first field effect transistor 132. Amplified microwave and high frequency signals applied from the input terminal IN to the output terminal OUT. In addition, the power amplifier 130 receives the switching control signal CTL # from the controller 106 at the time of reception, and when the first switch 120 is turned off, the power amplifier 130 is connected between the input terminal IN and the output terminal OUT. Since it is electrically disconnected, signal isolation with the transmitter can be secured.

Referring to FIG. 5, the second switch 122 is connected to the low noise amplifier 140. Of course, the second switch 122 and the low noise amplifier 140 may be provided as one device.

The low noise amplifier 140 includes an input terminal IN for inputting microwave and high frequency signals received from the antenna 102 and an output terminal OUT for suppressing, amplifying and outputting noise of the received microwave and high frequency signals. Low noise second field effect transistor (Low Noise FET) 142 or a high frequency (Monolithic Microwave Integrated Circuits: MMIC). The second field effect transistor 142 is also provided as an N-channel MOSFET.

The low noise amplifier 140 has an input terminal IN connected to the gate terminal of the second field effect transistor 142 and an output terminal OUT connected to the drain terminal of the second field effect transistor 142. The low noise amplifier 140 also includes blocking capacitors C7 and C8 between the input terminal IN and the gate terminal, and between the drain terminal and the output terminal OUT.

The low noise amplifier 140 is provided with a second switch 122 between the drain terminal of the second field effect transistor 142 and the terminal V _D applying the drain voltage. In the low noise amplifier 140, a third bypass circuit 154 and a third impedance converter 144 are provided in series between the second switch 122 and the drain terminal. Here again, the third bypass circuit 154 is provided with noise canceling capacitors C9 and C10, and the third impedance converter 144 is provided with a λ / 4 transmission line.

Therefore, when the low noise amplifier 140 receives the switching control signal CTL of the controller 106 when the second switch 122 is on, a drain voltage is applied to the second field effect transistor 142. The microwave and high frequency signals input from the input terminal IN are suppressed and amplified and output to the output terminal OUT. In addition, the low-noise amplifier 140 may ensure isolation by cutting off the second switch 122 and transmitting the input terminal IN and the output terminal OUT during transmission. Here, the first and second switches 120 and 122 are each provided in a CMOS FET type.

As another example, each of the first and second switches 120 and 122 may be damaged by an overcurrent applied to the power amplifier 130 or the low noise amplifier 140, as shown in FIG. 6. At least two switches 120a and 120b may be arranged in parallel.

Subsequently, an operation of the transceiver of the present invention will be described with reference to FIGS. 7 to 9.

FIG. 7 is a timing diagram for controlling a switching operation according to the TDD signal of the present invention, and FIG. 8 is a view comparing rising and polling times of the TDD signal according to the fast switching of the present invention.

Referring to FIG. 7, the TDD signal divides time into a transmission section Tx and a reception section Rx using the same frequency to transmit and receive data. Accordingly, the controller 106 of the present invention outputs the switching control signal CTL for turning on the first and third switches 120 and 110 in the transmission section Tx in response to the TDD signal, and simultaneously the second switch 122. Outputs a switching control signal (CTL #). In addition, a switching control signal CTL for outputting a switching control signal CTL for turning on the second and third switches 122 and 110 in the reception section Rx in response to the TDD signal, and simultaneously for turning off the first switch 120 ( CTL #).

Accordingly, as shown in FIG. 8, the transmitting and receiving device 100 of the present invention (b) has a rising time (Tr) and a falling time (Tf) of several hundreds of milliseconds, as shown in FIG. 1. It is possible to process at a higher speed than several hundred microseconds of the transmission and reception apparatus 10 of the conventional scheme (a).

As described above, the transmitter / receiver 100 according to the present invention secures the low noise amplifier 140 in the TDD-type wireless communication system 2 and secures the isolation during transmission and reception. Noise can be prevented from entering the furnace.

In addition, the transmitting and receiving device 100 of the present invention by using a high output switching device (120, 122) to control the high-speed switching operation according to the transmission, it can be implemented as a switching device of lower cost than the conventional method, accordingly high output high speed Data transfer is possible.

9 is a flowchart illustrating a processing procedure of a transmission / reception apparatus using a time division duplex method according to the present invention.

Referring to FIG. 9, in step S200, the controller 106 determines whether the transmission or reception intervals Tx and Rx correspond to the TDD signal. As a result of the determination, if the transmission period Tx of the TDD signal, the flow advances to step S210 to turn on the first switch 120, turn off the second switch 122, and simultaneously transmit the third switch 110 to the transmitter 160. ) To control the switching. As a result, the power amplifier 130 is driven in step S220 to process the transmission of the TDD signal.

As a result of the determination, if the reception period Rx of the TDD signal is reached, the process proceeds to step S230, where the first switch 120 is turned off, the second switch 122 is turned on, and the third switch 110 is simultaneously received. ) To control the switching. Therefore, in step S230, the low noise amplifier 140 is driven to process the reception of the TDD signal.

In the above, the configuration and operation of the time division duplex transmission and reception apparatus using the high-speed switching according to the present invention has been shown according to the detailed description and drawings, but this is merely described by way of example, and do not depart from the spirit of the present invention. Various changes and modifications are possible within the scope.

1 is a block diagram showing a schematic configuration of a transmission and reception apparatus using a time division duplex method according to an embodiment of the prior art;

2 is a block diagram showing a schematic configuration of a wireless communication system including a transmitting and receiving apparatus using a time division duplex scheme according to the present invention;

3 is a block diagram showing the configuration of a time division duplex transmission and reception apparatus according to the present invention;

4 is a circuit diagram showing a connection configuration of a first switch and a power amplifier shown in FIG. 3;

5 is a circuit diagram showing a connection configuration of a second switch and a low noise amplifier shown in FIG. 3;

6 is a circuit diagram showing a configuration according to another embodiment of the first or second switch shown in FIG. 4 or FIG.

7 is a timing diagram for controlling a switching operation according to the TDD signal of the present invention;

8 is a view comparing rising and polling times of a TDD signal according to a fast switching of the present invention; And

9 is a flowchart illustrating a processing procedure of a transmission and reception apparatus using a time division duplex method according to the present invention.

Explanation of symbols on the main parts of the drawings

2: wireless communication system 4, 8: server

6: repeater 100: transceiver

102: antenna 104: application

106: controller 108: local oscillator

110, 112, 120, 122: switch 114, 116: variable attenuator

118: circulator 124, 126: mixer

130: power amplifier 134, 136, 144: impedance converter

140: low noise amplifier 150, 152, 154: bypass circuit

Claims (12)

In the time division duplex transceiver device: A power amplifier provided in the transmission unit for transmitting the time division duplex type microwave and the high frequency signal to the antenna and amplifying the transmitted microwave and the high frequency signal; A low noise amplifier provided in the receiving unit for receiving the time division duplex type microwave and high frequency signals from the antenna, and suppressing and amplifying low noise of the received microwave and high frequency signals; A first switch coupled to the power amplifier and switching to drive the power amplifier upon transmission; And a second switch connected to the low noise amplifier and configured to switch the low noise amplifier to be driven when received. The method of claim 1, The transceiver device; A third switch provided at an input end and switching to select the transmitter or the receiver; A circulator provided on the antenna side and operative to select the transmitter or the receiver; And the first and the third switch are simultaneously switched so that the transmitter is activated during transmission, and the second and the third switch are simultaneously switched so that the receiver is activated upon reception. The method according to claim 1 or 2, The power amplifier comprises a first field effect transistor; And the first switch is connected to the drain terminal of the first field effect transistor. The method of claim 3, wherein The transceiver device; And a first bypass circuit is further provided between the first switch and the first field effect transistor. The method of claim 4, wherein The first field effect transistor; And a bias terminal connected to the gate terminal to bias the voltage, and a second bypass circuit is provided between the bias terminal and the gate terminal. The method of claim 5, The low noise amplifier comprises a second field effect transistor; And the second switch is connected to the drain terminal of the second field effect transistor. The method of claim 6, The transceiver device; And a third bypass circuit is further provided between the second switch and the second field effect transistor. The method of claim 7, wherein And a first impedance converter is further provided between the drain terminal of the first field effect transistor and the first bypass circuit. The method of claim 8, And a second impedance converter is further provided between the drain terminal of the second field effect transistor and the third bypass circuit. The method according to claim 1 or 2, The transceiver device; Electrically connected to the first to third switches to turn on the first switch, turn off the second switch, and turn off the third switch in response to microwave and high frequency signals in a time division duplex manner. And a controller configured to control switching to be connected to a transmitter, to turn on the second switch, to turn off the first switch, and to control the third switch to be connected to the receiver. . In the transmission and reception switching method of a time division duplex transceiver device: The transceiver includes a first switch connected to a power amplifier provided in a transmitter, a second switch connected to a low noise amplifier of a receiver, a third switch switched to be connected to a transmitter or a receiver, and a circulator connected to an antenna. Including, Switching control to connect the third switch to the transmitter during transmission, turn on the first switch, turn off the second switch, and switch control to connect the third switch to the receiver upon reception; And simultaneously turning on the second switch and turning off the first switch to process data transmission. The method of claim 11, The transmission and reception switching method; Operating the power amplifier when the first switch is turned on, and operating the low noise amplifier when the second switch is turned on.

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