KR20140028093A - Radar detector - Google Patents

Abstract

The present invention relates to a radar detector for detecting radio frequency signals. The radar detector includes: a receiving unit which receives radio frequency signals from the outside; a first detection circuit which detects continuous-type frequency signals among the received radio frequency signals; a second detection circuit which is composed as a separate circuit from the first detecting circuit and receives pulse-type frequency signals among the received radio frequency signals; and a detection unit which determines reception of the radio frequency signals based on signals provided from the first and the second detection circuits. According to the present invention, by providing a radar detector capable of detecting continuous-type radio frequency signals in various bands as well as detecting both continuous-type and pulse-type radio frequency signals, responsiveness to various kinds of external signals can be improved.

Description

Radar detector {RADAR DETECTOR}

The present invention relates to a radar detector for detecting a radio frequency signal, and more particularly to a radar detector capable of detecting various types of radio frequency signals.

Some countries, including the United States, use radio frequency signals to provide vehicles with road information, such as railroad crossings, under construction, and emergency vehicles, to induce safer driving or to generate radio frequency signals. The speed gun is used to measure the speed of the vehicle.

The radio frequency signal transmitted from the outside is detected using a radar detector provided in the vehicle. In general, the radar detector receives an external radio frequency signal and demodulates the received signal using various circuits. Then, it is determined whether the radio frequency signal is received based on the demodulated signal, and if the received signal is a valid signal instead of noise, information about the received signal is output to the user. The structure of such a detector is also disclosed in the publication of Korean Patent Laid-Open No. 2001-0011247.

In recent years, the frequency and pattern of radio frequency signals transmitted to vehicles have been gradually varied according to regions and applications. On the other hand, the conventional radar detector is installed only suitable for a specific radio frequency signal, there is a limit in detecting a variety of radio frequency signals.

Korean Patent Publication No. 2001-0011247 (issued Feb. 15, 2001)

The present invention is to provide a radar detector capable of detecting radio frequency signals of various patterns by providing a plurality of detection circuits for detecting radio frequencies in order to solve the above problems.

In order to achieve the above object, the present invention provides a receiver for receiving a radio frequency signal from the outside, a first detection circuit for detecting a continuous frequency signal among radio frequency signals received from the receiver, and separate from the first detection circuit. A second detection circuit configured to detect a pulsed frequency signal among radio frequency signals received from the receiver, and whether the radio frequency signal is received based on signals provided by the first detection circuit and the second detection circuit. It provides a radar detector comprising a detection unit for determining.

Here, the second detection circuit includes a log detector (logarithmic detector), wherein the pulsed frequency signal applied to the second detection circuit is configured to be converted into a direct current signal by the log detector.

Here, the log detector may be configured to convert a radio frequency signal having a frequency band in the range of 0.1 GHz to 3 GHz into a direct current signal.

The second detection circuit further includes a pulse variator for increasing a pulse width of the DC signal generated by the log detector.

The second detection circuit may be configured to detect a pulsed frequency signal having a duration time of 100 nm or less, and the pulsed frequency signal may have a spacing between adjacent signal pulses of 10 Hz or more. The pulsed frequency signal detected by the second detection circuit may be a signal having a higher output than the continuous frequency signal detected by the first detection circuit.

Furthermore, it is also possible to further include an intermediate frequency converter for converting the radio frequency signal received from the receiver into an intermediate frequency band. The intermediate frequency converter includes a first mixer and a first local oscillator, and is configured to mix the radio frequency signal received from the receiver and the frequency generated by the first local oscillator. Furthermore, the intermediate frequency converter may further include a sweep generator coupled to the first local oscillator.

The first detection circuit includes a second mixer, a filter unit, a demodulator, and an AD converter.

On the other hand, an object of the present invention described above is a receiver for receiving a radio frequency signal from the outside, a first mixer for generating an intermediate band frequency signal by mixing the frequency signal received by the receiver with a frequency signal generated in the first local oscillator A first detection circuit for amplifying the mixed signal in the first mixer, a first detection circuit for detecting a continuous frequency signal among the signals amplified in the first amplifier, and a pulse type among the signals amplified in the first amplifier Also achieved by a radar detector including a second detection circuit for detecting a frequency signal and a processor for determining whether to receive the radio frequency signal based on signals provided by the first detection circuit and the second detection circuit. Can be.

Here, the second detection circuit increases the pulse width of the log detector for converting the pulsed frequency signal into a DC signal, the third amplifier for amplifying the DC signal converted by the log detector, and the pulse width of the DC signal amplified by the third amplifier. It may be configured to further include a pulse variable.

According to the present invention, by providing a radar detector capable of detecting continuous radio frequency signals of various bands as well as both continuous radio frequency signals and pulsed radio frequency signals, responsiveness to various external signals Can be improved.

1 is a block diagram showing the structure of a radar detector according to a preferred embodiment of the present invention;
2 is a graph showing a waveform of a continuous radio frequency signal;
3 is a graph showing waveforms of a discontinuous radio frequency signal;
4 is a graph schematically illustrating a process of detecting a radio frequency signal provided to a second detection circuit.

Hereinafter, a radar detector according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the present embodiment, a radar detector installed in a vehicle will be described. However, the present invention is not limited thereto, and the present invention can be widely applied to a radar detector for various uses for detecting radio frequency signals provided from the outside.

Meanwhile, in the following description, the positional relationship of each component will be described based on the drawings in principle. The drawings may be simplified for simplicity of the description or exaggerated when necessary. Therefore, the present invention is not limited thereto, and it is needless to say that various devices may be added, changed or omitted.

1 is a block diagram showing the structure of a radar detector according to a preferred embodiment of the present invention.

As shown in FIG. 1, the radar detector 10 according to the present embodiment includes an intermediate frequency conversion for converting a frequency of a radio frequency signal received by the receiver 100 and a radio frequency signal received by the receiver 100. The unit 200 is connected to the intermediate frequency converter 200 and includes a first detection circuit and a second detection circuit for detecting a radio frequency signal. The processor 500 determines whether the radio frequency signal is received based on the signals provided from the first detection circuit 300 and the second detection circuit 400.

Specifically, the receiver 100 is configured of an antenna for receiving a radio frequency signal transmitted from the outside. The receiver 100 of the present exemplary embodiment is configured using a horn antenna as an example, but various antenna structures such as a patch antenna may be used.

The radio frequency signal received by the receiver 100 is converted into an intermediate frequency band by the intermediate frequency converter 200. In general, the radio frequency signal received by the radar detector is a high frequency of several tens of GHz or more, and the intermediate frequency converter 200 converts the high frequency into a signal in the frequency range of several hundred MHz to several GHz. Therefore, the intermediate frequency converter 200 contributes to improving the selectivity of the frequency and improving the sensitivity in processing the received radio frequency signal.

The intermediate frequency converter 200 includes a first mixer 210 and a first local oscillator 220. The first local oscillator 220 generates a frequency signal corresponding to a predetermined frequency band, and the first mixer 210 generates a radio frequency signal received by the receiver 100 and a frequency generated by the first local oscillator 220. Mix the signals. Accordingly, the intermediate frequency converter 200 may lower the frequency of the radio frequency signal received by the receiver 100 by the frequency of the signal generated by the first local oscillator 220.

Here, the intermediate frequency converter 200 further includes a sweep generator 230 connected to the first local oscillator 220. Accordingly, the first local oscillator 220 generates a frequency signal in a predetermined fundamental frequency range f1 and f2 by a sweeping operation of the sweep oscillator 230. In addition, the first local oscillator 220 generates a frequency signal corresponding to a harmonic of a source frequency, for example, a frequency signal having a frequency range of [2f1, 2f2] and [3f1, 3f2].

In general, the frequency range of the signal to be detected by the vehicle radar detector mainly includes the X band (8-12 GHz), the K band (18-27 GHz) and the Ka band (27-40 GHz). Among the major countries such as the United States and Russia, the frequency used to provide vehicle speed measurement and road information corresponds to 10.525 GHz in the X band, 24.150 GHz in the K band and 33.4 to 36 GHz in the Ka band.

Therefore, the source frequencies [f1, f2] of the first local oscillator 220 may be determined in consideration of various frequency bands to be received from the outside. For example, the source frequencies [f1, f2] correspond to radio frequency signals in the X band, the first harmonics [2f1, 2f2] correspond to radio frequency signals in the K band, and the second harmonics [3f1, 3f2] It may be determined to correspond to the radio frequency signal of the Ka band. Therefore, even when a radio frequency signal of any band of the X band, the K band, and the Ka band is received, the first mixer 210 mixes with the source frequency signal generated by the first local oscillator 220 or its harmonic signal to a predetermined range. It can be converted to include the frequency signal of.

In this embodiment, the first local oscillator 220 is configured to have a source frequency of 10.97 ~ 11.39 GHz. Therefore, the above-described radio frequency signals of the X band and the K band Ka band are respectively mixed with the source frequency signal, the first harmonic signal, and the second harmonic signal of the first local oscillator in the first mixer, respectively, and have an intermediate band frequency of 3 GHz or less. Is converted to include the signal. However, the source frequency of the first local oscillator of the present embodiment is just one example, and may be variously designed in consideration of the frequency characteristics of the frequency signal to be detected.

As described above, the radio frequency signal converted to the intermediate band frequency is amplified by the first amplifier 240 and applied to the first detection circuit 300 and the second detection circuit 400, respectively.

2 is a graph showing waveforms of a continuous radio frequency signal, and FIG. 3 is a graph showing waveforms of a discontinuous radio frequency signal.

 In general, the radio frequency signal received from the outside is a continuous signal in which radio frequency signals having a constant frequency are continuously provided as shown in FIG. 2. In contrast, in the radio frequency signal illustrated in FIG. 3, a pattern in which a high frequency signal is not provided for a second time T2 after a high frequency signal of a constant frequency is provided for a first time T1 is repeated. Accordingly, the pulsed radio in which the signal pulse P1 is provided during the first time T1 and the next signal pulse P2 is provided after the second time T2 has elapsed after the corresponding signal pulse P1 is terminated. Form a frequency signal.

Recently, in the case of a pulsed radio signal frequency applied to a speed gun, a high frequency signal of 24.150 GHz is provided for a time of 100 ns or less to form one signal pulse P. Then, when one signal pulse P is terminated, the pattern in which the high frequency signal is not provided is repeated for 10 Hz or more, and 25-30 Hz for more relief. Thus, a signal pulse P having a duration of 100 ns is provided at a frequency of 30 to 40 KHz.

As such, the pulsed radio frequency signal is provided with a signal pulse only for a very short time compared to the continuous radio frequency signal. The pulsed radio frequency signal to be detected by the vehicle detector has a larger output than the continuous radio frequency signal. Due to such different signal characteristics, detecting a continuous radio frequency signal and a pulsed radio frequency signal using one detection circuit can significantly reduce either detection capability.

Accordingly, the radar detector according to the present invention includes at least two detection circuits, and is configured to detect the continuous radio frequency signal and the pulsed radio frequency signal in separate detection circuits. Hereinafter, each detection circuit will be described in detail with reference to the accompanying drawings.

First, the first detection circuit 300 is a configuration for detecting a continuous frequency signal among radio frequency signals received by the receiver 100. As shown in FIG. 1, the first detection circuit 300 is connected to the intermediate frequency converter 200. Therefore, the continuous frequency signal is provided to the first detection circuit 300 in a state converted by the intermediate frequency converter 200, and detected by using various circuit elements included in the first detection circuit 300.

In detail, the first detection circuit 300 may include a second amplifier 310, a second mixer 320, a filter unit 360, a demodulator 370, and an AD converter 380. .

Here, the second amplifier 310 amplifies the output of the continuous radio frequency signal converted by the intermediate frequency converter 200.

The signal amplified by the second amplifier 310 is transferred to the second mixer 320. The second local oscillator 330, the third local oscillator 340, and the fourth local oscillator 350 may be connected to the second mixer 320. The plurality of local oscillators are provided in the second mixer 320 to convert the frequencies so that the above-mentioned radio frequency signals of the various bands may pass through one filter unit 360. Accordingly, the second local oscillator 330 of the present embodiment corresponds to the X band radio frequency signal, the third local oscillator 340 corresponds to the K band radio frequency signal, and the fourth local oscillator 350 is Ka band radio. It may be configured to correspond to the frequency signal.

For this reason, when the radio frequency signal of the X band passes through the intermediate frequency converter 200 and converts the frequency, the second mixer 320 is mixed with the oscillation frequency of the second local oscillator 330 and the filter unit 360. The frequency is converted to pass through. The radio frequency signals of the K band and the Ka band are similarly mixed with the oscillation frequency of the third local oscillator 340 and the oscillation frequency of the fourth local oscillator 350 in the second mixer 320, respectively. The frequency is converted to pass through 360.

As an example, the second local oscillator 330 of the present embodiment is configured to generate a single frequency in the range of 500 to 600 MHz, and the third local oscillator 340 is configured to generate a single frequency in the range of 1500 to 1600 MHz. The fourth local oscillator 350 may be configured to generate a single frequency in the range of 2000 to 2200 MHz.

As described above, since the radar detector 10 according to the present embodiment is designed to receive radio frequency signals of the X band, the K band, and the Ka band among the continuous radio frequency signals, three local oscillators may include the second. According to the structure connected to the mixer 320 or the use of the radar detector 10, the number of local oscillators connected to the second mixer 320 and the oscillation frequency of each local oscillator may be changed.

As described above, the frequency-converted signal through the second mixer 320 selectively filters only a signal having a specific frequency band, and a demodulation unit that detects a signal passing through the filter unit 360 ( 370 and the AD converter 380 for converting the demodulated signal into a digital signal sequentially. Accordingly, the continuous radio frequency signal passing through the first detection circuit 300 is converted into a digital signal and provided to the processing unit 500, whereby the processing unit 500 receives the continuous radio frequency signal through the receiving unit 100. Can be detected.

On the other hand, the second detection circuit 400 is a configuration for detecting a pulsed frequency signal of the radio frequency signals received by the receiver 100. As shown in FIG. 1, the second detection circuit 400 is connected to the intermediate frequency converter 200. Accordingly, the pulsed frequency signal among the radio frequency signals is provided to the second detection circuit 400 in a state converted by the intermediate frequency conversion unit 200, and the second detection circuit 400 uses various circuit elements. Detect the signal.

4 is a graph illustrating a process of detecting a radio frequency signal provided to the second detection circuit. The second detection circuit includes a logarithmic detector 410, a third amplifier 420, and a pulse variator 430. Hereinafter, the second detection circuit 400 is configured using FIG. 4. It demonstrates concretely about.

The log detector 410 provided in the second detection circuit 400 is a circuit element for converting a radio frequency signal into a direct current signal. The log detector 410 requires that the output of the input radio frequency signal is equal to or greater than a predetermined value, but has an advantage of excellent detection characteristics with respect to time. Accordingly, the second detection circuit 400 may detect whether a pulsed radio frequency signal is received by using the characteristics of the log detector 410.

In this embodiment, in consideration of the pulse-type frequency signal characteristics to be detected by the vehicle radar detector, a log detector 410 that can convert a frequency signal in the 0.1 ~ 3 GHz band to a direct current signal is used. In addition, the log detector 410 may use a device capable of converting and outputting a DC signal even when the length of the radio frequency signal is 100ns or less.

Accordingly, the pulsed radio frequency signal received by the receiver 100 is input to the log detector 410 as a pulsed radio frequency signal whose frequency is converted through the intermediate frequency converter 200 (see FIG. 4A). The log detector 410 converts the pulsed radio frequency signal into a direct current signal and outputs a pulsed direct current signal (see b in FIG. 4).

Meanwhile, the third amplifier 420 is connected to the log detector 410. Then, the pulsed DC signal output from the log detector 410 is amplified (see c of FIG. 4).

At this time, the pulsed DC signal amplified by the third amplifier 420, as in the pulsed radio frequency signal received at the receiver, the duration of the signal pulse P is very short, 100ns or less. Therefore, when such a signal pulse is provided to the processing unit as it is, there is a fear that it may not be recognized depending on the performance of the processing unit.

Therefore, the second detection circuit 400 of the present embodiment further includes a pulse variator 430 for increasing the pulse width of the input signal. The pulse variable 430 converts the pulse width of the pulsed DC signal output from the third amplifier 420 to increase (see d of FIG. 4). Therefore, the second detection circuit 400 may convert the signal into a form easily determined by the processing unit 500 and provide the signal to the processing unit.

As described above, the first detection circuit 300 detects the continuous radio frequency signal, the second detection circuit 400 detects the pulsed radio frequency signal, and provides each result to the processing unit 500. do.

On the other hand, the processor 500 is composed of a processor that can output arithmetic and control signals. The processing unit 500 is connected to the first detection circuit 300 and the second detection circuit 400. Then, it is determined whether the continuous radio frequency signal is received based on the signal input from the first detection circuit 300, and whether or not the pulse type radio frequency signal is received based on the signal input from the second detection circuit 400. Judge.

The processor 500 determines whether the radio frequency signal is received from the outside and the type of the received radio frequency signal in the same manner as above, and based on this, the audio or video output circuit (not shown) provided in the radar detector 10 is used. It is possible to control and provide the vehicle driver with the information by the radio frequency signal.

In the present embodiment, the process of passing the continuous radio frequency signal through the first detection circuit and the process of passing the pulsed radio frequency signal through the second detection circuit are described, but the continuous radio frequency signal and the pulsed radio frequency signal are described. May be provided as both the first detection circuit and the second detection circuit. However, it is difficult to detect the continuous radio frequency signal in the second detection circuit because the magnitude of the received signal is weak, and the pulse type radio frequency signal has a very short input time of the signal pulse to detect it through the first detection circuit. it's difficult. Therefore, the description of the present embodiment will be found centering around the effective detection circuit according to the shape of the frequency signal.

As described above, the radar detector according to the present embodiment separately includes a first detection circuit for detecting a continuous radio frequency signal and a second detection circuit for detecting a pulsed radio frequency signal. Therefore, various radio frequency signals can be detected using one radar detector, and an optimized detection corresponding to the characteristics of each radio frequency signal is possible.

100: receiver 200: intermediate frequency converter
300: first detection circuit 400: second detection circuit
410: log detector 430: pulse variable
500 processing unit

Claims (1)

Receiving unit for receiving a radio frequency signal from the outside;
A first detection circuit for detecting a continuous frequency signal of the radio frequency signals received from the receiver;
A second detection circuit comprising a circuit separate from the first detection circuit and processing a pulsed frequency signal among radio frequency signals received from the receiver; And
And a processor configured to determine whether to receive the radio frequency signal based on the signals provided from the first detection circuit and the second detection circuit.
The intermediate frequency converter further comprises a sweep generator coupled to the first local oscillator.

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