TW201110059A - Electrical toll collection system with terminal limiting communication zone - Google Patents

Abstract

The electrical toll collection system (ETCS) with terminal limiting communication zone disclosed in this invention is applicable for an electrical toll collection system of an on board unit (OBU) having an antenna, an RF receiving component, an RF transmitting component, and a baseband transceiving component, wherein a transceiving performance limiting device of the OBU is also included. The transceiving performance limiting device of the OBU includes a digital control block and an RSSI control block for limiting the receiving performance of the OBU on the receiving terminal of the ASK demodulator of the RF receiving component, and performing transmitting or receiving operations only within a certain communication area. This invention effectively addresses the issues of noise that is generated outside the communication area and affects ETCS and the lowered conversion efficiency of receiving and transmitting mechanisms when entering the OBU communication area in the prior art technology.

Description

201110059 VI. Description of the Invention: [Technical Field] The present invention is a communication area limiting device of a TCS terminal, and the ETCS terminal of the present day and the day can obtain the communication area of the high-end etcs terminal by the collection energy of the precision machine ETCS terminal. Internal communication success rate. [Prior Art] Electronic Toll C〇llection System (hereinafter referred to as "ETCS") is also called highpass system, which is a non-stop charging system using 5 8ghz wireless communication system. The Intdligem Transport System (hereinafter referred to as "ITS"), which is the result of environmental pollution and the computerization of the transportation system, constitutes a basic unit. The above ETCS communication system uses the Amplitude Shift Keying ("ASK") method of 5.8 GHz bandwidth, and there are two types, passive and active, in which active ETCS and ITS can be easily implemented. Figure 1 is a general structural diagram of an electronic toll collection system. Referring to FIG. 1 , an electronic toll collection system (Electric Toll Collection System 201110059, ETCS) includes an On Board Unit (hereinafter referred to as “〇Bu”), a first vehicle detector 120, and a second vehicle detector 125. , R〇ad Side Equipment (hereinafter referred to as “RSU1”) 13〇 and second roadside unit (R〇ad

Side Equipment ’ hereinafter referred to as “RSU2”) 135. The OBU 110, as a terminal mounted on the vehicle, can perform RF (RadioFreqUency) signaling or receiving operations with the RSUs 130 and 135 installed on the road side. The functions of the above-described vehicle detectors 120, 125 are only for identifying the type of vehicle, and are not related to the transmission or reception of RF. The above-described 〇BU 11〇 will sequentially pass through the first vehicle detector 120, the second vehicle detector 125, the first roadside unit 1181; 113〇 and the first roadside unit RSU2 135 and complete the steps required for charging. The section indicated by the arrow in the first figure indicates the communication area 15A, and the section can perform a transmission or reception operation between the OBU 110 and the RSUs 13, 135, and is optimal according to the road condition. And it will not be changed after installing etcs on the road side.

...the above-mentioned health 150 is strictly locked in a region of a certain size in order to minimize the occurrence of ETCS malfunction, and adjusts the output of 130 135 to the output and the antenna offset according to the demand. After the sex, the required cage (9) can be formed. The above-mentioned health feed is beyond the position of the first vehicle detector 12, and if the area outside the communication area 150 (for example, the front of the first vehicle detector 120) is performed, the OBU 110 and the RSU 130, 135 are The letter is sent to the letter t, the job is lying wrong. That is to say, only when the above (10) ΠΚ) and the above-mentioned RSUs 13A and 135 are transmitted or propagated inside the communication area 150, it means that the operation is normal. Therefore, in order to comply with the above-mentioned communication area 150' of the ETCS 201110059, the above-mentioned OBU 110 must have good performance, and the lower the receiving performance of the 〇bu 110 for the above-mentioned predetermined communication area 150, the higher the possibility that the ETcs operation is erroneous. Brother 2 is the preferred implementation of the electronic charging system or the receiving department - an example. Please refer to FIG. 2'. The previous ETCS includes an antenna 1〇〇, an Rp transmitting unit 2〇〇, and a Baseband transmitting and receiving unit 300. The above-described transmitting and receiving unit 200 includes an RF receiving unit 210, an Rp transmitting unit 22, and an RF switch 230. The RF receiving unit 210 includes an L〇W Noise Amplifier 212, a Down Conversion Mixer 214, a Filter 216, and an ASK Demodulator 218. The Low Noise Amplifier 212 described above can amplify the RF signal. The D〇wn Conversion Mixer 214 can convert the amplified RF signal to an IF (Intermediate Frequency) signal by performing a Down conversion. The Filter 216 can filter the noise of the signal after the Down conversion. The ASKDemodulator 218 demodulates the received signal in an ASK (Amplitude Shift Keying) manner, and then outputs the digital signal to the Baseband transmitting and receiving unit 300. The RF transmitting unit 220 includes an Up Conversion Mixer 222 and a Power Amplifier 224. The Up Conversion Mixer 222 can convert the input signal from the Baseband transmitting and receiving unit 300 into an RP signal, and the Power Amplifier 224 can convert the RF signal into a signal having a desired output level. 201110059 The second figure above omits the influence of the VCO (Voltage Controlled Oscillator) and PLL (Phase Locked Loop) ° Figure 3 on the vehicle's performance (OBU) performance on the communication success rate of the electronic toll collection system. Please refer to FIG. 3 and FIG. 1 '350 for the minimum communication success rate in the communication area 150, 310 for the communication success rate when the OBU 110 transmission performance exceeds the reference, and 330 for the OBU 110 to receive the lower communication performance. The communication success rate at the time of the reference, 320 indicates the communication success rate when the transmission performance of the OBU 110 conforms to the reference to form an optimization. The above 350 indicates that the communication success rate of the ETCS terminal is lower than the minimum communication success rate, and the ETCS terminal is regarded as a failure. The above 310 indicates that the receiving performance of the 〇BU 110 is good and exceeds the reference so that the sector outside the communication area, that is, the location before the vehicle detector 1 120 is sent. The above 330 indicates that the receiving performance of the OBU 110 is lower than the reference, and a section 340 in which the internal communication success rate of the k-zone has dropped sharply before leaving the communication zone will occur. At this time, if the OBU 110 passes through the ETCS section at a high speed, the possibility of an error increases a lot. The receiving performance of the OBU 110 of the above 320 does not exceed the communication area 15〇, and the section of the communication success rate 150 does not appear in the communication area 150. Therefore, it can be stabilized when the OBU 110 passes at a high speed. Performance. Figure 4 is a diagram showing the output signal of the 〇Bu transmitter obtained after the performance of the transmitter of the previous 〇BU is reduced. In the month of the month, see the picture of the brother 4 and the first picture. The left picture of the picture 4 is the output signal diagram of the general 〇bu signaling unit 201110059. The output signal of the OBU 110 is the signal after modulation (Modulation) according to the ASK method, and the output value thereof. Need to exceed a certain size. The quality of the above output ## can be expressed using Modulation Index 412, which is the difference between the carrier portion 410 and the amplitude offset portion 414. The smaller the difference between the above-mentioned amount 410 and the above-mentioned amplitude offset component 414, the better the Modulati〇n Index 412' also indicates that the quality of the output signal of the BU 11 〇 output signal is excellent. The right diagram of Fig. 4 is an output signal diagram of the 〇Bu no signal obtained after the performance of the transmitting portion of the OBU 110 is reduced. As can be seen from the above figure, the Modulation Index 422 can be lowered when the magnitude of the amplitude offset component 424 is reduced while the carrier portion 42 〇 remains unchanged. By reducing the performance of the above-mentioned M〇dulati〇nIndex422 by reducing the 0BU丨1〇 signaling signal, the performance of the RSU 130 and 135 can be reduced, so that the receiving performance of the RSU 130 and 135 can be reduced, so that it can be limited. ^ Communication area 150 between 130 and 135. '

The above prior art can be used for the reward zone, but has the following problems.丄 即 ’ 删 删 删 删 (10) 110 action mode is as long as the receipt of the letter will be the heart. Therefore, it is not possible to limit the performance of the receiving part of the OBU 110. (10) The receipt of the ιι〇: can be confirmed before the receipt of the entry into the health (10) _ will also be positive & ^ ’ OBU 110 will also be rotated. That is to say, the communication between the area before the communication area = _10 and Na 130, the ratio is unsuccessful, and the _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ The noise will also reduce the conversion efficiency of receiving and sending letters at 150 people in the Tongren District. SUMMARY OF THE INVENTION It is an object of the present invention to provide a communication area limiting device of £1:(8 terminal), which can electrically control the receiving sensitivity of an ETCS terminal in a limited communication area. The communication area limiting device of the ETCS terminal of the present invention is applicable to an electronic toll collection system having an antenna, an RF receiving unit, a welcoming transmitting unit, and an on-board (OBU) of the transmitting and receiving unit, wherein the receiving performance of the 〇BU is included. Limiting device, the receiving performance limiting device of the OBU has Digital c〇ntrol

Block and RSSI Control Block ' can be in the ask that constitutes the above rf receiving part

The receiving end of the Demodulator limits the receiving performance of the above-mentioned BU and performs the sending or receiving operation only in a certain range of communication areas. The communication area limiting apparatus of the ETCS terminal of the present invention for achieving the above object can be applied to an electronic toll collection system having an antenna, an RF receiving unit, an RF transmitting unit, and an on-board (OBU) of the Baseband transmitting and receiving unit, including 0BU. a receiving performance limiting device, the receiving performance limiting device of the OBU has Digital c〇ntr〇1 B1〇ck and

The RSSI Control Block ' can be aSK that constitutes the above rf receiving part

The receiving end of the Demodulator limits the receiving performance of the above 〇 311 and only performs signaling or receiving operations within a certain range of communication areas. [Embodiment] In order to make the objects, features, and advantages of the present invention more apparent, the following description of the accompanying drawings is set forth below. Fig. 5 is a structural diagram of a communication area limiting device of the ETCS terminal of the present invention. Referring to FIG. 5 and FIG. 2, the communication area limiting apparatus of the present invention can be configured as an on-board (OBU) having an antenna 100, an RF transmitting and receiving unit 200, a Baseband transmitting and receiving unit 300, and an OBU terminal memory 400 in 201110059. Electronic toll collection system. The above-described transmitting and receiving unit 200 includes a receiving performance limiting device 240 for the onboard computer in addition to the previous RF receiving unit 210, the RF transmitting unit 220, and the RF switch 230. The above-described receiving performance limiting means 240 is a circuit corresponding to the characterizing portion of the present invention and can limit the receiving performance of the OBU, including the Digital Control Block 242 and the RSSI Control Block 244. The above RSSI Control Block 244 is a RSSI that can be correspondingly sized according to the size of the received signal (Received

Signal Strength Indicator) The circuit that outputs the signal, which can be controlled by Digital Control.

Block 242 is adjusted. The RSSI Control Block 244 described above is adjusted by the Digital Control Block 242 to adjust the wheeled signal of the ASK Demodulator 218 based on the adjusted RSSI threshold or the best value of the reference sensitivity. The above output 彳§ is transmitted to the Baseband transmitting and receiving unit 300. At this time, the optimal Digital Control Value of the RSSI threshold or the reference s sensitivity is stored in the obu terminal memory 400. The antenna 100, the RP transmitting and receiving unit 2, and the Baseband transmitting and receiving unit 300 have been described in FIG. 2 and will not be described in detail herein. Figure 6 is a diagram showing the operation of the OBU receiving performance method of the present invention. Referring to Figures 6 and 5, 610 indicates that the reference reception sensitivity ’ 611 of the 〇BU indicates that the RSSI ’ 620 indicates that the RSSI threshold (RSSIth) 613 indicates the RSSI inclination (s1〇pe). The above-mentioned reference reception sensitivity 61〇 applies to 201110059. When it is between individual turns, it is necessary to maintain a very small sensitivity sensitivity deviation. The RSSI threshold 620 is a reference value that can measure whether the size of the received signal of 〇BlJ is greater than or less than the RSSI threshold 620, and can be adjusted by the above RSSI c〇1 B1〇ck 244. - Figure 7 is the rSSI generated by the operation of the receiving performance of the 〇BU of the present invention.

ASK output signal after Demodulation. Referring to Fig. 7 and Fig. 5, 610 indicates the reference reception sensitivity φ of the OBU (Pre Magic, indicating RSSI '740 indicates the ASK output signal after Demodulation. The above RSSI 730 is generated by the above RSSI Control Block 244, receiving p When the number is greater than the corresponding rssI threshold RSSIthl of the reference reception sensitivity 61〇, the Logic Level High' receiving signal is smaller than the RSSI threshold RSSIth1, and becomes the Logic Level Low. The output js No. 740 is only received at the 〇BU. When the signal size is larger than the corresponding RSSI threshold RSSIth2 of the reference receiving sensitivity 610, the output is not generated when the size of the receiving signal is smaller than the RSSI threshold RSSIth2. The communication area limiting device of the present invention is applicable in the embodiment. 〇 BU, can also be applied to the RSU as needed. This is very obvious. When the communication area limiting device is applied to the RSU, the 〇Bu method described in the above 5th to 7th drawings can be used, that is, The communication area of the RSU can be limited by the adjustment operation of the RSSI slope 611 or the RSSI threshold RSSIth, and therefore will not be described in detail. The summary is as follows. First, the user can pass the rSSi 201110059 adjusted by Digital ControlBlock242.

Control Block 244 adjusts the RSSI slope 611 and the RSSI threshold RSSIth2 to fine tune the receiving sensitivity of the 〇BU to the desired level (Level) to limit the sending and receiving of jobs between the OBU and the RSU. The communication area 150 is internally 〇 second, and the RSSI Control Block 244 can be controlled as follows by the RSSI 630 function. For an input signal lower than the reference reception sensitivity 610, a demodulation output signal is not generated in the receiving portion of the 〇BU, and an OBU transmission output signal is generated only when the reference reception sensitivity 610 is greater than the reference reception sensitivity 610. . Third, the communication area limiting device of the present invention is adjusted by the digital control method. Therefore, the automatic calibration (Auto-Calibration) function can be realized when the 0BU is created, and the RSSI valve obtained through the experimental method can be obtained in the OBU production process. Optimal digital control value for value or reference reception sensitivity (Digkal

Control Value) is stored in the 0BU terminal memory 4, so it can be easily operated. 4. The above-mentioned pass restriction device is not only applicable to 〇Bu, but also applicable to RSU. In this case, the above-mentioned method applicable to 〇Bu can be used. The present invention has been described in detail by the preferred embodiments of the invention, and is not intended to limit the scope of the invention, and the present invention may be used as various changes and modifications without departing from the spirit and scope of the invention. The scope of protection of the date of issue is subject to the definition of the scope of the patent application. [Simple description of the diagram] Figure 1 is a general description of the electronic toll collection system (ETCS). Figure 2 is a diagram showing the preferred implementation of the transmitting or receiving section of the previous electronic toll collection system. Figure 3 is an explanatory diagram of the effect of the performance of the on-board (0BU) on the communication success rate of the electronic toll collection system. Fig. 4 is a diagram showing the output signal of the 〇BU transmitting unit obtained by reducing the performance of the transmitting unit of the previous OBU. Fig. 5 is a structural diagram of a communication area limiting device of the ETCS terminal of the present invention.

Fig. 6 is a view showing the milk illusion of the OBU's receiving performance operation method of the present invention. Fig. 7 is an RSS output signal generated by the RSSI and Demodulation generated by the reception performance operation of the obu of the present invention. [Main component symbol description]

214 Filter 216 Antenna 100 First Vehicle Detector 120 First Road Side Unit B0 Communication Area 150 RF Receiver Unit 210 Down Conversion Mixer ASK Demodulator 218

Up Conversion Mixer 222 RF Switch 230 Digital Control Block 242

Baseband sending and receiving department 300 OBU terminal memory 400 car machine 110 second car auxiliary detector 125 second road side unit 135 RF transmitting and receiving unit 200

Low Noise Amplifier 212 RF Transmitter 220

Power Amplifier 224 Receive Performance Limiter 240 RSSI Control Block 244 Section 340 Carrier Part Size 410 12 201110059

Modulation Index 412 Amplitude Offset 5 414 Modulation Index 422 Offset Partition 424 Baseline Receive Sensitivity 610 RSSI 611 RSSI Threshold 620 RSSI Slope 613 RSSI 730 ASK Output Signal 740

Claims (1)

201110059 VII. Patent application scope: 1 · A communication area restriction device for ETCS terminals, suitable for electronic devices with antennas, receiving parts, RF transmitting parts and Baseband sending and receiving parts (〇BU). The system, wherein the receiving performance limiting device includes 0Bu, the receiving performance limiting device of the OBU has a Digital Control Block and an RSSI Control Block, and the OBU can be restricted on the receiving end of the ASK Demodulator constituting the RP receiving unit. The receiving performance is performed only in a certain range of communication areas for sending or receiving jobs. 2. The communication area limiting device of the ETCS terminal according to claim 1, wherein the RSSI Control Block adjusts the RSSI threshold or the RSSI inclination to control the amplitude offset key generated by the ASK Demodulator. (ASK) output signal. 3. The communication area limiting device of the ETCS terminal according to item 2 of the patent application scope, wherein the amplitude offset key system (ASK) output signal is only in the input signal strength (Inputpower) of the above-mentioned 〇BU is greater than the above The corresponding reference reception sensitivity (Pref) of the RSSI threshold is output. 4. The communication area limiting device of the iETCS terminal according to claim 1, wherein the RF transmitting unit transmits the signaling signal only when the corresponding reference receiving sensitivity (Pref) is greater than the RSSI threshold. 201110059 5. The communication area limiting device of the ETCS terminal according to claim 1, wherein one of the baseband transmitting and receiving sections is additionally provided with a digit that can store the RSSI threshold or the reference receiving sensitivity (pref). OBU terminal memory of the Control Value (Digital Control Value). 6. A communication area limiting device for an ETCS terminal, which is suitable for an electronic charging system having an antenna, an RF receiving unit, an RF transmitting unit, and a Baseband transmitting and receiving unit installed on each of the roadside units (RSUs), wherein The RSU receiving performance limiting device includes a Digital Control Block and an RSSI Control Block, and the roadside unit (RSU) can be restricted on the receiving end of the ASK Demodulator constituting the RF receiving unit. The receiving performance is only performed in a certain range of communication areas for sending or receiving operations. 7. The communication area limiting device of the ETCS terminal according to claim 6, wherein the RSSI Control Block performs the rounding of the RSSI threshold or the RSSI inclination to control the amplitude offset key generated by the ASK Demodulator. System (ASK) turns out the signal. 8. The communication area limiting device of the ETCS terminal according to claim 6, wherein the amplitude offset key (ASK) output signal is only greater than the RSSI valve of the received signal input strength (lnputpower) of the above obu. The value is output when the corresponding reference reception sensitivity (Pref) is used. 15 201110059 9. If the patent application is for the communication area restriction device of the iETCS terminal mentioned in item 6, the above-mentioned issue. .发送 Only send the signal when the corresponding reference of the RSSI threshold is greater than the above-mentioned RSSI. σ.10, please refer to the communication area limiting device of the ETCS terminal as described in Item 6 One end of the Baseband transmitting and receiving unit is additionally provided with an RSU terminal memory capable of storing a digital control value of a φ RSSI threshold or a reference receiving sensitivity (Pref). 16