KR100429262B1 - Appliance for radio frequency of Road Side Equipment of Dedicated Short Range Communication - Google Patents

Abstract

In the present invention, in a short range wireless communication base station of an intelligent transportation system (ITS), in particular, local oscillation is applied to a PLL type to facilitate channel scan and change. The high frequency device of the short range wireless communication base station according to the present invention A high frequency switch for selecting a path according to a transmission and reception mode when communicating with a vehicle terminal; A receiving unit which receives the received high frequency signal as a near field radio frequency signal, converts the received high frequency signal into a local oscillation signal, converts it into an intermediate frequency, and demodulates received data; A transmitter which modulates the transmission data into a local oscillation signal and then amplifies and outputs the power through the high frequency switch; And a local oscillator for generating and outputting a local transmission signal of a short range wireless communication frequency band on a transmission / reception path.

According to the present invention, by applying the local oscillator applied by the crystal oscillator and the PLL module in the high frequency part on the transmission and reception path, the channel scan and channel change of the base station, which was not possible in the conventional high frequency device of the DRO type, can be applied to various services. The present invention provides a short range wireless communication base station that can cope with the problem.

Description

High frequency device of near field communication base station {Appliance for radio frequency of Road Side Equipment of Dedicated Short Range Communication}

The present invention relates to a short range wireless communication base station in a short distance wireless communication base station of an intelligent transportation system, in particular, by sharing two PLL modules with a crystal oscillator and a PLL module for transmitting and receiving a high frequency part of a wireless communication base station. It relates to a high frequency device.

ITS (Intelligent Transport System) is a new transportation system that improves the mobility, stability, efficiency and the traffic environment by integrating the existing transportation system with advanced technologies such as information communication, electronics, control, and computers. It is aimed at reducing congestion, reducing traffic accidents, expanding the use of public transportation, and reducing logistics costs.

Dedicated Short Range Communication (DSRC), which is introduced to provide such intelligent transportation system services, is a communication system composed of a roadside base station and a vehicle terminal (vehicle mounting device) located on a roadside.

The short range wireless communication means is a small output device supporting the TDMA / TDD scheme of the 5.8 GHz band having a communication distance of 100M or less and a transmission rate of 1 Mbps. It accommodates all ITS services.

The high frequency device of the conventional short range wireless communication base station is as shown in FIG.

Referring to FIG. 1, a high frequency switch 110 for switching a transmission mode and a reception mode path when communicating with a vehicle terminal through an antenna 100, and a frequency received from the high frequency switch 110 in a reception mode as an intermediate frequency. A receiver 120 for converting and demodulating a data signal, a transmitter 130 for modulating transmission data and outputting the modulated data through the high frequency switch 110, and frequency tuning of the receiver 120 and the transmitter 130 during data transmission and reception. It consists of a local oscillator 140 for outputting a local outgoing signal for.

Here, the receiver 120 includes a first bandpass filter 121 for filtering a 5.8 GHz band of a reception frequency, and a low noise amplifier (LNA) for amplifying a low noise signal of the filtered frequency signal (LNA). 122, a frequency converter 123 for mixing the output frequency of the low noise amplifier 122 with a local oscillation signal to convert the intermediate frequency, a second band pass filter 124 for filtering the intermediate frequency band, and An intermediate frequency amplifier 125 for amplifying the intermediate frequency signal, and a demodulator 126 for demodulating the data signal from the amplified intermediate frequency signal.

The transmitter 130 includes a data filter 131 for filtering data into a predetermined band signal, an amplitude sequence keying (ASK) modulator 132 for modulating the filtered data signal into a local oscillation signal, and the ASK. And a third bandpass filter 133 for filtering the modulated signal to the 5.8 GHz band, and a power amplifier 134 for power amplifying the signal filtered by the third bandpass filter 133.

The local oscillator 140 may include a first dielectric resonator oscillator (DRO) generating a reception frequency of 5.8 GHz and a local oscillation signal to the frequency converter 123 by amplifying the reception frequency. A second driving amplifier 142 for outputting a signal, a second dielectric resonance oscillator 143 for generating a transmission frequency of 5.8 GHz, and amplifying the generated transmission frequency and outputting the local oscillation signal to the ASK modulator 132. The second drive amplifier 144 is composed of.

Referring to the accompanying drawings, a high frequency device of a conventional short-range wireless communication base station as described above is as follows.

First, in the transmission mode, the high frequency switch 110 is switched to the receiver side, and when a signal transmitted from the vehicle terminal is received by the antenna 100, the received signal (5.8 GHz) is output to the receiver 120.

The receiver 120 mixes the reception frequency with the local oscillation signal to make the intermediate frequency IF and demodulates the received data.

To this end, the first bandpass filter 121 of the receiver 120 filters the received frequency to the 5.8 GHz band and removes other band signals. The low noise amplifier 122 amplifies low noise to improve noise characteristics, and the frequency converter 123 converts the frequency output from the low noise amplifier (LNA) 122 into an intermediate frequency by mixing with a local oscillation signal. The two band pass filter 124 filters only the intermediate frequency band. The intermediate frequency amplifier 125 amplifies the filtered intermediate frequency and the demodulator 126 demodulates the received data signal from the intermediate frequency.

In the transmission mode, the data filter 131 of the transmitter 130 filters the input data signal, and the ASK modulator 132 modulates the data signal with a local oscillation signal at a frequency of 5.8 GHz and uses a third band pass. The filter 133 filters the required 5.8 GHz band among the frequencies modulated by the ASK modulator 132, and amplifies and outputs the power to the power amplifier 134.

Then, the transmission signal output from the power amplifier 134 of the transmitter 130 is transmitted to the terminal through the antenna 100 in the switching switching of the high frequency switch 110 to work in accordance with the transmission mode.

On the other hand, the local oscillator 140 generates transmit and receive local oscillation signals according to the transmission and reception mode, and outputs them to the receiver 120 and the transmitter 130, respectively. The first dielectric resonance oscillator (DRO) 141 is 5.8 GHz band. Generates a reception frequency (5.87 GHz), and the driving amplifier 142 amplifies the reception frequency and outputs the received local oscillation signal to the frequency converter 123.

In addition, the second dielectric resonator oscillator (DRO) 143 generates a transmission frequency (5.8 GHz) of 5.8 GHz, and the second driving amplifier 144 amplifies the transmission frequency and then uses an ASK modulation unit (ASK) as a local oscillation signal. 132) to modulate the transmission data.

However, in the related art, the dielectric resonator oscillators 141 and 143 generating oscillation frequency in the local oscillator 140 are installed in different transmission and reception paths and generate 5.8 GHz band, but the dielectric resonator oscillators 141 and 143 have their volume. Large, only factory-set fixed channels are available, and channel scans and changes are not possible, so only fixed channels are always available.

In addition, the size of the high frequency part (RF part) is increased by the external size of the dielectric resonator oscillators 141 and 143, and it acts as an important factor that separates the control part from the high frequency part in all base stations.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a high-frequency device of a short range wireless communication base station to tune a transmission / reception frequency by applying a temperature compensated crystal oscillator and a PLL module to a transmission / reception path, respectively. There is this.

It is an object of the present invention to provide a local oscillation apparatus of a short range wireless communication base station that can share an expensive high frequency amplifier and a multiplier using a high speed switch to output a frequency output from a PLL module.

1 is a block diagram of a high frequency device of a conventional short-range wireless communication base station.

2 is a block diagram of a high frequency device of a short range wireless communication base station according to the first embodiment of the present invention;

3 is a block diagram of a high frequency device of a short range wireless communication base station according to the second embodiment of the present invention;

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

100,200,300 ... antenna 110,210,310,349 ... high frequency switch

120,220,320 ... receiver 130,230,330 ... transmitter

140,240,340 ... Local Oscillator 141,143 ... DRO

142,144,244,254,247,257 ... Amplifiers

242,252,341 ... Temperature Compensated Crystal Oscillators

243,253,342,343 ... PLL module 245,255,346 ... multiplier

246,256,347 ... Bandpass Filters

In order to achieve the above object, a high frequency device of a short range wireless communication base station according to the present invention,

A high frequency switch for selecting a path according to a transmission and reception mode when communicating with a vehicle terminal;

A receiving unit for receiving the received high frequency signal as a near field radio frequency signal, mixing the local oscillation signal, converting it into an intermediate frequency, and demodulating the received data;

A transmitter which modulates the transmission data into a local oscillation signal and then amplifies and outputs the power through the high frequency switch;

And a local oscillator for generating and outputting a local transmission signal of a short range wireless communication frequency band on a transmission / reception path.

Preferably, the local oscillator comprises a plurality of crystal oscillators for generating reference frequencies for PLL operation on transmission and reception paths, a plurality of PLL modules for operating at the PLL reference frequencies and generating transmission and reception frequencies, respectively; A high frequency amplifier for amplifying transmission and reception oscillation frequencies generated from the PLL module, a multiplier for multiplying the frequency generated from the high frequency amplifier, a bandpass filter for filtering the multiplication frequency to a short range wireless communication frequency band, and the band And a drive amplifier for amplifying the pass filtered frequency and outputting transmit and receive local oscillation signals.

Preferably, the local oscillator comprises a crystal oscillator for generating a PLL reference frequency on a single path, a plurality of PLL modules for generating a transmission and reception frequency by the reference frequency, and the transmission and reception frequencies according to a transmission / reception mode. A high frequency switch for fast switching output, a high frequency amplifier for amplifying the switched transmission and reception oscillation frequency components, a multiplier for multiplying the amplified transmission and reception oscillation frequencies, and a short range wireless communication band based on the multiplication frequency; A bandpass filter, a driving amplifier for amplifying the bandpass filtered required frequency, and an output switch for switching the transmission or reception frequency amplified and output from the driving amplifier according to a transmission / reception mode and outputting each as a local transmission / reception signal. It is characterized by.

Hereinafter, with reference to the accompanying drawings as follows.

2 is a block diagram of a high frequency device of a short range wireless communication base station according to the first embodiment of the present invention, and FIG. 3 is a block diagram of a high frequency device of a short range wireless communication base station according to the second embodiment of the present invention.

Referring to FIG. 2, a high frequency switch 210 for switching a transmission / reception path of short-range wireless data transmitted and received to and from a vehicle terminal through an antenna 200, and converts a received high frequency signal into an intermediate frequency by a local oscillation signal and receives received data. A receiver 220 for demodulating the signal; A transmission unit 230 for modulating the transmission data into a local oscillation signal, amplifying the power to a high frequency of 5.8 GHz, and outputting the power to the high frequency switch 210; The local oscillator 240 outputs a transmission and reception local oscillation signal using the temperature compensation crystal oscillators 242 and 252, the PLL modules 243 and 253, and the multipliers 244 and 254 according to the transmission and reception modes.

Here, the local oscillator 240 is a temperature compensation crystal oscillator (TCXO, 242, 252) for generating a PLL reference frequency in the transmission and reception mode, and PLL modules (243, 253) for generating a transmission frequency and a reception frequency by the PLL reference frequency. A high frequency amplifier (244,254) for amplifying the generated frequency, a multiplier (245,255) for multiplying the amplified frequency, a fourth bandpass filter (246, 256) for filtering the multiplier frequency to a 5.8 GHz frequency band; And driving amplifiers 247 and 257 for amplifying the bandpass filtered frequency to output a local oscillation signal.

3 is a second embodiment of the present invention.

The PLL frequency generated from the transmission and reception PLL modules 342 and 343 can be shared according to the transmission / reception mode so that the high frequency amplifier 345, the multiplier 346, the bandpass filter 347, and the driving amplifier 348 can be shared on a single path. A switching high frequency switch 344 and an output switch 349 for switching the amplified transmission and reception local oscillation signals amplified from the driving amplifier 308 according to a transmission / reception mode and outputting them to the reception unit 310 or the transmission unit 320. It is a configuration to include.

Referring to the accompanying drawings, a high frequency device of a short range wireless communication base station according to an exemplary embodiment of the present invention will be described.

Referring to FIG. 2, the high frequency switch 210 converts a signal transmitted through the antenna 200 and a received signal according to a transmission / reception mode to the receiver 220 and the transmitter 230 for short range wireless communication with the vehicle terminal. Connected.

In the reception mode, a transmission signal of the vehicle terminal is received through the antenna 200, the received high frequency signal is applied to the receiver 220 through the high frequency switch 210, and the receiver 220 receives the first high frequency signal. The bandpass filter is performed by the bandpass filter 221 and low noise amplified by the low noise amplifier 222.

The frequency converter 223 mixes the received high frequency signal with the local oscillation frequency to convert the intermediate frequency, and the intermediate frequency converted by the frequency converter 233 is filtered by the bandpass filter 234 to filter only the intermediate frequency component. After amplification by the intermediate frequency amplifier 235, the demodulator 236 demodulates the received data (1 Mbps).

In the transmission mode, the transmission data is modulated to the local oscillation frequency in the transmission unit 230 and then transmitted to the vehicle terminal through the high frequency switch 210 and the antenna 200.

The data filter 231 of the receiver 230 filters digital data (1 Mbps) to be transmitted, and the ASK modulator 232 modulates the transmitted data into the local oscillation signal, and then, the third band pass filter 233. ) Bandpass filters the modulated frequency to the 5.8 GHz band, and the power amplifier 234 power amplifies the bandpass filtered frequency and outputs the amplified frequency to the high frequency switch 210.

On the other hand, the local oscillator 240 generates a local oscillation signal for synchronizing the transmission and reception signals of the transmission and reception unit 220, 230, the transmission frequency generation module 241 and the transmission frequency generation module 251 is provided for transmission And a local oscillation signal for transmission and reception of data in accordance with each mode on the reception path.

Transmit and receive frequency generation modules 241 and 251 are located on different transmit and receive paths, with temperature compensated crystal oscillators (TCXOs) 242 and 252, phase lock loop (PLL) modules 243 and 253 and high frequency amplifiers (244 and 254). , Multipliers (× 2) 245 and 255, band pass filters (BPFs) 246 and 256, and driving amplifiers 247 and 257, respectively.

The temperature compensated crystal oscillators 242 and 252 are one of the crystal applications, and generate a reference frequency for operating the PLL. The PLL modules 243 and 253 compare the phase of the PLL reference frequency and the oscillation frequency and use the difference to determine the frequency. And output the desired transmit and receive frequencies (2.9 / 2.935 GHz) respectively. The PLL modules 243 and 253 exist on transmit and receive paths TX and RX for time division duplex (TDD) communication in bidirectional communication.

The high frequency amplifiers 244 and 254 amplify the PLL oscillation frequency components generated from the PLL modules 243 and 253, and the multipliers 245 and 255 multiply the amplified frequencies by two and output them in the short range wireless communication band of 5.8 GHz.

That is, since the frequency of 2.9 GHz generated from the PLL modules 243 and 253 is multiplied and amplified by the multipliers 245 and 255 into the 5.8 GHz band, a local oscillation frequency for short range wireless communication is generated.

The fourth and fifth band pass filters 246 and 256 filter to remove other components except the 5.8 GHz frequency component among the signals multiplied by the multipliers 245 and 255, and the driving amplifiers 247 and 257 are filtered out. After amplifying a frequency in the 5.8 GHz band, the signals are output to the receiving unit 210 and the transmitting unit 230 as transmission and reception local oscillation signals.

Here, the transmission frequency (5.8 GHz) is about 70 MHz away from the reception frequency (5.87 GHz), and a 70 MHz frequency change occurs during transmission and reception.

As such, by placing the crystal oscillators 242 and 252 and the PLL modules 243 and 253 for transmission and reception on the transmission and reception paths respectively, and multiplying the PLL frequencies of the PLL modules 243 and 253 by the local oscillation frequency for short-range wireless communication, Generates the 5.8GHz band required for wireless communications.

In addition, since the PLL method is used for the local generator in the high frequency unit for the ITS roadside base station, the channel scan is possible, and thus the channel can be easily changed, and the base station channel installed in the center can be remotely controlled and various services are provided.

Second embodiment;

Referring to FIG. 3, the receiver 320 filters the signal input from the high frequency switch 310 in the reception mode with the first bandpass filter 321, low noise amplifies the noise with the low noise amplifier 322, and then frequency. The converter 323 converts to an intermediate frequency by a local oscillation signal. After filtering by the second band pass filter 324, the amplification is performed by the intermediate frequency amplifier 325, and the demodulator 326 demodulates the received data (1 Mbps).

The transmitter 330 filters the transmission data (1 Mbps) with the data filter 331, modulates the filtered data into the local oscillation signal by the ASK modulator 332, and then transmits the filtered data to the third band pass filter 333. By bandpass filtering, the power amplifier 334 performs power amplification and transmits a transmission signal (5.8 GHz) to the high frequency switch 310.

On the other hand, the local oscillator 340 generates the transmit and receive PLL frequencies by operating the PLL modules TX and RX 342 and 343 by the PLL reference frequencies generated by the temperature compensation crystal oscillator 341.

In this case, the high frequency switch 344 is interlocked with the high frequency switch 310 and converts the transmission and reception frequencies (2.9 / 2.935 GHz) generated from the plurality of PLL modules 342 and 343 into high speed switching according to the transmission and reception modes. In the transmission mode, it is connected to the transmitter. In the reception mode, it is connected to the receiver.

The high frequency amplifiers 345 amplify the PLL frequency components output from the high frequency switch 344, and the multiplier 346 multiplies the amplified frequency by two and outputs the short range wireless communication frequency in the 5.8 GHz band.

Then, the bandpass filter 347 filters and outputs only the required 5.8GHz band of the amplified signals, and the driving amplifier 348 amplifies the bandpass filtered 5.8GHz required frequency.

Then, since the output switch 349 interworking with the high frequency switch 310 has the bandpass filtered frequency connected to the transmitting side or the receiving side, the output switch 349 outputs a local oscillation signal to the receiving unit 320 or the transmitting unit 330. In this case, the output switch 309 switches the transmission / reception frequency within a short time for TDD (Time Division Duplex) communication.

Then, the received local oscillation frequency output from the output switch 349 of the local oscillator 340 is synchronized with the high frequency signal received by the receiver 320 and modulated to an intermediate frequency, and the transmit local oscillation signal is based on the transmission data in the short range radio frequency band. Modulate with.

This second embodiment transmits and receives PLL modules 342 and 343 on a single path to share the high frequency amplifier 345, the multiplier 346, the bandpass filter 347, and the drive amplifier 348 from the first embodiment. The local oscillation unit by switching the transmission and reception frequencies generated from the &lt; RTI ID = 0.0 &gt;) &lt; / RTI &gt; to the high frequency switch 344 and quickly switching the transmission or reception frequency amplified by the drive amplifier 345 so that the output switch 349 is suitable for the TDD scheme. The local oscillation signal of 340 is output to the receiver 310 and the transmitter 320 to perform bidirectional data transmission and reception.

As described above, according to the high-frequency device of the short-range wireless communication base station according to the present invention, the local oscillator applied by the crystal oscillator and the PLL module is installed on a single path, thereby making it possible to perform channel scan and change which were impossible in the conventional DRO type. As a result, the base station channel can be remotely controlled and can cope with various services.

In addition, as the volume of the local oscillation portion of the PLL type decreases, the size of the high frequency device is also reduced, making it easy to install and maintain, and improve the cost competitiveness of the high frequency device.

Claims (3)

A high frequency switch for selecting a path according to a transmission and reception mode when communicating with a vehicle terminal; A receiving unit for receiving the received high frequency signal as a near field radio frequency signal, mixing the local oscillation signal, converting it into an intermediate frequency, and demodulating the received data; A transmitter which modulates the transmission data into a local oscillation signal and then amplifies and outputs the power through the high frequency switch; Generating and outputting a local outgoing signal of a short range wireless communication frequency band in a PLL scheme on a transmit / receive path; A plurality of crystal oscillators generating reference frequencies for PLL operation on a transmit and receive path, a plurality of PLL modules operating on the PLL reference frequency and generating transmit and receive frequencies respectively, and transmit and receive generated from the PLL module A high frequency amplifier for amplifying the oscillation frequency, a multiplier for multiplying the oscillation frequency generated from the high frequency amplifier, a bandpass filter for filtering the multiplication frequency into a short range wireless communication band, and amplifying and transmitting and receiving the bandpass filtered frequency A local oscillation unit comprising a driving amplifier for outputting a local oscillation signal; A high frequency device of a short range wireless communication base station comprising a. delete The method of claim 1, The local oscillator comprises a crystal oscillator for generating a PLL reference frequency on a single path, a plurality of PLL modules for generating transmission and reception frequencies according to the reference frequency, and high speed switching of the transmission and reception oscillation frequencies according to a transmission / reception mode. A high frequency switch for outputting, a high frequency amplifier for amplifying the switched output and received oscillation frequency components, a multiplier for multiplying the amplified transmission and reception oscillation frequencies, and a bandpass for filtering a short range wireless communication band based on the multiplication frequency A filter, a driving amplifier for amplifying the bandpass filtered required frequency, and an output switch for switching the transmission or reception frequency amplified and output from the driving amplifier according to a transmission / reception mode and outputting each as a local transmission / reception signal. High frequency of near field communication base station Device.