KR20010056858A - Apparatus for transmitting and receiving radio frequency in electronic toll collection system - Google Patents

Abstract

PURPOSE: A wireless signal transmitting and receiving instrument used for automatically collecting the toll fee is provided, thereby the identification of cars and collection of the toll fee can be rapidly performed. CONSTITUTION: The wireless signal transmitting and receiving instrument consists of a high frequency signal receiving and processing part which receives wireless signal from antenna, removes image noise, and converts high frequency signal into middle frequency signal; a middle frequency signal processing part which processes middle frequency signal received from the high frequency signal receiving and processing part, and extracts and outputs signal; and a high frequency signal transmitting and processing part which transmits signals having car-receivable high frequency range.

Description

Wireless transceiver for automatic toll collection systems {APPARATUS FOR TRANSMITTING AND RECEIVING RADIO FREQUENCY IN ELECTRONIC TOLL COLLECTION SYSTEM}

The present invention relates to an automatic toll collection system that is being developed for a smooth flow of traffic, and more particularly, to a vehicle by smoothly transmitting and receiving a radio signal with a vehicle passing through a toll gate in a predetermined short time in the automatic toll collection system. The present invention relates to a wireless transceiver for an automatic toll collection system that enables data processing such as verification and toll collection.

Currently, a toll gate is installed to receive a predetermined fee from a driver who uses a highway or toll road. At the toll gate, a manpower is arranged to collect the fee by checking the vehicle at each entrance, and the fee depends on the distance used. Was collected. However, in this case, the driver temporarily stops the car at about the entrance and is approximately parallel with the toll collector, and then receives a predetermined sign from the toll collector and similarly the driver maintains the proper distance with the toll collector at the exit. After paying off, you must pay the bill to the bill collector, confirm the fee with the bill collector, and hand the fee back to the bill collector.

In this case, since all processes are performed manually, the passage time of the toll gate per vehicle becomes longer, and thus the problem of worsening congestion in modern times, in which vehicles increase, is increasing.

As a way to solve the congestion at these toll gates, an automatic ticket issuing device is used. When a vehicle enters the entrance, it automatically classifies the ticket indicating the starting point by classifying the vehicle as large or small according to the size of the vehicle. It is equipped with an automatic ticket issuing device for issuing. In this case, the driver draws the ticket by hand by bringing the vehicle close to the ticket issuing device, and at the exit side, the driver closes the toll collector and stops the vehicle as before. In addition, a proper fee must be handed to the toll collector along with the ticket issued at the entrance.

Therefore, it is effective in reducing congestion at the entrance side of the toll gate, but for beginners who are not good at driving, it is difficult to drive the vehicle close to the ticket issuing device, and it is inconvenient to feel the burden when entering the toll gate. In addition, there is a problem that the congestion at the exit side is still not solved. In addition, there is an inconvenience in that drivers must always prepare cash to pay the toll gate cost.

The present invention has been made to solve the above-mentioned problems, the object of the vehicle passing through the toll gate for a predetermined short time in order to be able to implement an automatic toll collection system that automatically checks and charges for passing vehicles; The present invention provides a wireless transceiver for an automatic toll collection system that can smoothly transmit and receive wireless signals to enable data processing such as vehicle identification and toll collection.

1 is a schematic configuration diagram for explaining an automatic toll collection system.

2 is a block diagram showing a detailed configuration of a wireless transmission and reception apparatus for an automatic toll collection system according to the present invention.

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

11: car 12: toll gate

20: first unit (wireless transceiver)

21: high frequency reception signal processing unit

22: intermediate frequency signal processing unit

23: high frequency transmission signal processing unit

As a configuration means for achieving the above object of the present invention, the present invention provides a wireless transmission and reception apparatus for an automatic toll collection system for automatically collecting charges by exchanging a predetermined radio signal for a vehicle traveling at a predetermined speed,

A high frequency reception signal processing unit for receiving a radio signal of a predetermined band received by an antenna and converting and outputting the demodulated intermediate frequency signal by removing image noise;

An intermediate frequency signal processor for processing an intermediate frequency signal input from the high frequency received signal processor and extracting and outputting a signal carried in a wireless signal;

And a high frequency transmission signal processor for transmitting a high frequency signal of a predetermined band that can be received by a unit on a vehicle side at a set cycle.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the radio transceiver in the automatic toll collection system according to the present invention.

1 is a schematic block diagram showing an example of an automatic toll collection system associated with a wireless transmission / reception apparatus according to the present invention, wherein the automatic toll collection system displays data indicative of vehicle-specific recognition information in a predetermined frequency band set in the vehicle 11. The first unit 10 to be transmitted is mounted, and the toll gate 12 transmits a signal of a predetermined natural frequency band set to a use band in a predetermined period through a wireless antenna ANT at regular intervals, and receives the received signal of the vehicle 11. The second unit 20, which is a high frequency module for receiving and processing the radio signal of the corresponding band transmitted from the unit 10, and the operation and alarm processing of the second unit 20 and the information received therefrom is transmitted to the central processing unit. It is made by mounting the third unit 30 for the purpose, the second unit 20 of the toll gate 12 continues to transmit the signal of the frequency set so that the passing vehicle can recognize, To the receiving wireless signals carried the vehicle information transmitted from the first unit 10 in the recognized vehicle 11 is only processed output signal corresponding to the vehicle information.

At this time, the wireless transmission / reception module such as the second unit 20 transmits a radio signal to a vehicle passing in a short time without stopping, and accordingly, the automatic toll collection system should be able to receive and process a signal sent from the vehicle without missing it. Implementation of.

The present invention relates to a wireless transmitting / receiving module such as the second unit 20 which is in charge of communicating with a vehicle passing through a toll gate which is most important for automatic toll collection in such an automatic toll collection system. As shown, a high frequency reception signal processor 21 for receiving a radio signal of a predetermined band (for example, 5.8 GHz) largely received by an antenna, converting and outputting the image noise into a demodulated intermediate frequency signal, and Intermediate frequency signal processing unit 22 for processing the intermediate frequency signal input from the high frequency reception signal processing unit 21 to extract and output the signal carried in the radio signal, and the high frequency signal of the set band that can be received by the unit on the vehicle side at a set cycle. It consists of the high frequency transmission signal processing part 23 which transmits.

In the above description, the high frequency reception signal processor 21 includes a first band pass filter 211 for passing only a signal of a set band among wireless signals received by the antenna, and a high frequency signal passed through the first band pass filter 211. A first band rejection filter 212 for removing the unwanted noise signal and two low noise amplifiers having two stages, and a first amplifier for amplifying a high frequency signal passing through the first band rejection filter 212 to a predetermined level A first alarm unit 214 which applies an amplifier 213 and a bias voltage for stable operation of the first amplifier 213 and checks this to output an alarm signal (Rx alarm signal) indicating that there is a received signal; A phase difference of 90 degrees between the second band rejection filter 215 for removing unnecessary noise included in the high frequency signal output from the first amplifier 213 and the high frequency signal output from the second band rejection filter 215. Split into two signals with The splitter 216 and the high frequency signal having a 90 degree phase difference output from the splitter 216 are mixed with the input local oscillating signal, respectively, converted into an intermediate frequency band (for example, 10 MHz), and then synthesized to produce image noise. And a coupler 218 for dividing the oscillation signal of the set band generated from the high frequency transmission signal processing section 23 into two and applying it to the mixer 217.

The intermediate frequency signal processor 22 may include second to fourth amplifiers 221, 223 and 225 to amplify the intermediate frequency signal output from the high frequency reception signal processor 21, and the second to fourth amplifiers 221, 223 and 225. A bias voltage is applied to the second and third band pass filters 222 and 224 and the second to fourth amplifiers 221, 223 and 225 respectively provided between the second and third band pass filters 222 and 224 to remove noise outside the intermediate frequency signal band output from each amplifier. A second alarm unit 226 which checks operation and alerts an operation state, and an FSK demodulation unit which outputs a baseband signal by FSK demodulating the intermediate frequency signal having passed through the multi-stage connected amplifier and band pass filter. 227, a third alarm unit 226 for applying a bias voltage to the FSK demodulator 227, checking for normal operation, and alarming, and an FSK demodulated base output from the FSK demodulator 227; Finally, the band signal (ie 1MHz) is amplified and output. Claim 5 comprises a amplifier 229.

In addition, the high frequency transmission signal processor 23 outputs an oscillator 231 for oscillating and outputting a signal of a frequency band set as a signal band used by the automatic toll collection system, and outputs a frequency signal oscillated by the oscillator 231. A synthesizer 232, a sixth amplifier 233 for amplifying the oscillation signal of the set band, a first bias circuit unit 234 for providing a bias voltage of the sixth amplifier 233, and the sixth amplifier A splitter 235 for dividing the high frequency signal of the set band output from the signal 233 into two and applying one to the coupler 218 of the high frequency received signal processor 21 and an on / off operation of the splitter 235. A switch 236 for applying or blocking other output signals of the switch, a switch controller 237 for controlling an on / off operation of the switch 236 according to an operating power source applied to a transmitter, and the switch 236. High frequency applied An attenuator 238 for attenuating the magnitude of the signal to a predetermined level, a seventh amplifier 239 for amplifying the high frequency transmission signal output from the attenuator 238 to a transmission level, and a bias voltage for the seventh amplifier 239. A second bias circuit unit 240 for applying a signal, a low pass filter 241 for attenuating a noise signal having a band higher than that of the high frequency transmission signal output from the seventh amplifier 239 and transmitting the same through an antenna, and the high frequency transmission The fourth alarm unit 242 detects the power level of the signal, checks whether it is in normal operation, and alerts.

As described above, in the present embodiment, the radio transceiver according to the present invention is designed to transmit and receive high frequency signals in the 5.8 GHz band.

That is, first, the high frequency transmission signal processor 23 transmits only the set frequency signal without any information so that the first unit 10 mounted on the vehicle passing through the toll gate passes through the automatic toll collection system. As shown in FIG. 2, the set reference frequency oscillated by the oscillator 231 is amplified to a predetermined level through the sixth and seventh amplifiers 233 and 239 biased by the first and second bias circuits 234 and 240, and is attenuated by the attenuator 238. After being attenuated to an appropriate level so as not to be overloaded, it is output to the antenna through a low pass filter 241 for attenuating harmonic signals that interfere with the transmission signal.

At this time, the high-frequency transmission signal is only to recognize the toll gate passing vehicle to transmit the magnetic information, it is unnecessary to operate continuously at all times, it can be a waste of power. Therefore, the high frequency transmission signal only needs to be transmitted at a predetermined period so that the vehicle passing through the toll gate can be received once before leaving the toll gate.

Accordingly, the high frequency transmission signal processing unit 23 turns on / off the switch 236 in accordance with the voltage control signal V-mod in the switch control unit 237 to apply or block the high frequency transmission signal to the antenna side.

Thus, a high frequency transmission signal is sent out every predetermined period.

At this time, the transmission of the high frequency transmission signal checks the power level of the signal output from the fourth alarm unit 242 to the antenna to determine whether the high frequency transmission signal unit 23 operates normally, and the result according to the determination is determined from the outside. Outputs an alarm signal (Tx alarm signal) to indicate.

As described above, when the first unit 10 in the vehicle 11 that receives the high frequency transmission signal transmitted at a predetermined cycle loads the information of the vehicle in the set frequency band, the high frequency reception signal processing unit 21 receives the information. The bandpass filter 211 filters the signal received by the antenna and outputs only a signal having a set frequency (5, 8 GHz), and the first band rejection filter 212 provided at the next stage After the first band pass filter 211 attenuates the signal of the predetermined frequency band that is not filtered, the first amplifier 213 amplifies the frequency signal of the set band thus received to a predetermined level so as to perform frequency conversion processing from the rear end. After attenuating the out-of-band noise signal that may be mixed during the amplification by the second band rejection filter 215, the second band rejection filter 215 may be input to the mixer 217 through the splitter 216. In the above, the splitter 216 separates and outputs the received high frequency signal into two signals having a 90 degree phase difference, and the mixer 217 is two mixers capable of performing frequency conversion processing on each of the two high frequency signals having a 90 degree phase difference. 217a and 217b and two low pass filters 217c and 217d, each of the two input signals is mixed with a local oscillation signal input from the coupler 218, and the mixed signal is mixed with the low pass filter 217c. , 217d), and converts the high-frequency signal of 5.8 GHz into an intermediate frequency signal of 10 MHz, and then synthesizes and outputs the synthesizer through the synthesizer 217e.

Accordingly, the high frequency reception signal processing unit 21 outputs a 10 MHz intermediate frequency signal carrying vehicle information. In the above, the normal operation of the high frequency reception signal processing unit 21 is checked by the first alarm unit 214 connected to the first amplifier 214, and the RX alarm signal is output to be known from the outside when the high frequency signal is received. .

The intermediate frequency signal is input to the intermediate frequency signal processor 22 and passes through a plurality of amplifiers and band pass filters 221 to 225 connected in multiple stages, and noises that may cause interference are removed and amplified to an appropriate level. Only the baseband signal corresponding to the vehicle information is outputted so that the demodulator 227 can be demodulated and digitally processed.

The normal operation of the amplifying stages 221 to 225 in the intermediate frequency signal processor 22 is checked by the second alarm unit 226, and the normal operation of the FSK demodulator 228 is performed by the third alarm unit 228. By checking in and outputting a predetermined alarm signal, it is possible to check whether the intermediate frequency signal processing unit 22 operates normally from the outside.

As described above, the wireless transmission / reception apparatus for transmitting a signal in a predetermined frequency band may allow a vehicle passing through a toll gate to communicate with a radio signal containing predetermined information while stopping automatically when the toll gate passes. This makes it possible to implement an automatic toll collection system that can automatically collect charges without stopping the vehicle, manipulating the driver or preparing cash.

Claims (4)

A wireless transceiver for an automatic toll collection system for automatically collecting charges by exchanging predetermined radio signals for a vehicle traveling at a predetermined speed, A high frequency reception signal processing unit for receiving a radio signal of a predetermined band received by an antenna and converting and outputting the demodulated intermediate frequency signal by removing image noise; An intermediate frequency signal processor for processing an intermediate frequency signal input from the high frequency received signal processor and extracting and outputting a signal carried in a wireless signal; A radio transmitting / receiving device for an automatic toll collection system, characterized by comprising a high frequency transmission signal processing unit for transmitting a high frequency signal of a predetermined band that can be received by a unit on a vehicle side at a set period. The method of claim 1, wherein the high frequency reception signal processing unit A first band pass filter for passing only a signal of a set band among wireless signals received by an antenna, a first band rejection filter for removing unnecessary noise signals included in a high frequency signal passing through the first band pass filter, and a second stage Two low-noise amplifiers consisting of a first amplifier for amplifying the high frequency signal passed through the first band rejection filter to a predetermined level, a bias voltage for the stable operation of the first amplifier is applied to check the received signal A first alarm unit for outputting an alarm signal for indicating a signal, a second band rejection filter for removing unnecessary noise included in the high frequency signal output from the first amplifier, and a high frequency signal output from the second band rejection filter A splitter for splitting the signal into two signals having a phase difference of 90 degrees, and a high frequency signal having a 90 degree phase difference output from the splitter. And a coupler which divides the oscillation signal of the set band generated from the high frequency transmission signal processing unit into two and mixes it with the local oscillation signal, converts it into an intermediate frequency band, synthesizes it, and removes image noise. Wireless transmission and reception device for an automatic toll collection system characterized in that. The method of claim 1, wherein the intermediate frequency signal processing unit Second to fourth amplifiers for amplifying the intermediate frequency signal output from the high frequency reception signal processing unit, and second to remove noise outside the intermediate frequency signal band provided between each of the second to fourth amplifiers; A third band pass filter, a second alarm unit which applies a bias voltage to the second to fourth amplifiers and checks the normal operation and alerts the operation state, and the intermediate frequency of the set frequency band passing through the multi-stage connected amplifier and the band pass filter. An FSK demodulator for FSK demodulating and outputting a frequency signal as a baseband signal, a third alarm unit for applying a bias voltage to the FSK demodulator and checking whether it is in normal operation and an alarm, and outputting from the FSK demodulator And a fifth amplifier for finally amplifying the FSK demodulated baseband signal to output the amplified baseband signal. The method of claim 1, wherein the high frequency transmission signal processing unit A frequency synthesizer for oscillating and outputting a signal of a set frequency band by oscillation, a sixth amplifier for amplifying the oscillation signal of the set band, a first bias circuit unit for providing a bias voltage of the sixth amplifier, and the sixth amplifier A divider for dividing the high frequency signal of the set band output from the two into one and applying it as a local oscillation signal to the high frequency reception signal processor; a switch for turning on / off the other output signal of the divider; A switch control unit for controlling the on / off operation of the switch according to the operating power applied to the attenuator, an attenuator for reducing the magnitude of the high frequency transmission signal applied through the switch to a predetermined level, and a high frequency transmission signal output from the attenuator. A seventh amplifier for amplifying the output level and a second bias circuit for applying a bias voltage to the seventh amplifier; A low pass filter that attenuates noise signals in a band higher than the high frequency transmission signal output from the seventh amplifier, and transmits them through an antenna, and detects the power level of the high frequency transmission signal to check normal operation and alarms Wireless transmission and reception apparatus for an automatic toll collection system, characterized in that consisting of a fourth alarm unit.