JPH10256928A - Method and device for super-regenerative reception, remote control receiver, and remote control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the degradation of the reception sensitivity due to the temperature change or the aged deterioration and to improve S/N by varying a resonance frequency and a quenching oscillation frequency and automatically controlling these frequencies. SOLUTION: When a system consists of a super-regenerative circuit 3 consisting of a high frequency oscillator 5 which varies the resonance frequency, a quenching oscillator 6 which caries the quenching oscillation frequency, and a low pass filter 7, a level detector which detects the output level of the super- regenerative circuit 3, and a control part 9, the control part 9 adjusts the quenching oscillation frequency to set a wide band characteristic at the time of waiting for reception and adjusts the resonance frequency to equalize a reception carrier frequency and a tuning frequency at the time of starting reception so that the output level of the level detector is a fixed value. Thereafter, the control part 9 adjusts the quenching oscillation frequency to set a narrow band characteristic. When reception is terminated in this state, the quenching oscillation frequency is adjusted again to set a wide band characteristic.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a super-reproduction receiving apparatus and method for performing super-reproduction detection, and a remote control receiver and a remote control system using the ultrasonic receiving apparatus.

[0002]

2. Description of the Related Art A super-regenerative detection method is one of the detection methods of a receiver (for example, disclosed in Japanese Patent Publication No. 54-5609). Generally, the super regenerative detection method has a feature that a high sensitivity can be obtained while the configuration is simpler than other detection methods.

FIG. 1 shows a configuration example of a super regenerative receiver having a super regenerative circuit. The signal received by the antenna 1 of the receiver is amplified by the high-frequency amplifier 2 and the amplified signal is guided to the super-regeneration circuit 3 for detection. The detection signal thus obtained passes through the low-frequency amplifier 4 and is converted into binary data of 0 and 1 by a comparator and output to the signal processing unit.

[0006] The super-regeneration circuit 3 has a frequency resonance section, and comprises a high-frequency oscillator 5 tuned to a reception carrier frequency, a quenching oscillator 6, and a low-pass filter 7.

[0005]

In the above-mentioned conventional super regenerative circuit, if the characteristics of the elements of the super regenerative circuit, especially the elements in the high-frequency oscillator 5 including the tuning frequency resonating portion change due to temperature change or aging change. In addition, there has been a problem that a shift occurs in the tuning frequency and the sensitivity of the entire super-reproduction circuit is reduced. In addition, since the reception sensitivity characteristic is fixed, the S / N is reduced when the characteristic is set to a wide band, and when the characteristic is set to a narrow band, the sensitivity is greatly changed due to a small change in the tuning frequency. There has been a problem of causing a decrease.

SUMMARY OF THE INVENTION An object of the present invention is to make the resonance frequency and the quenching oscillation frequency variable, and to automatically control these frequencies so that the reception sensitivity does not deteriorate with respect to temperature change and aging, and S / S An object of the present invention is to provide a super-reproduction receiving apparatus and method capable of improving both N and communication quality and reliability, and a remote control receiver and a remote control system to which the apparatus is applied.

[0007]

The invention according to claim 1 is
A super regenerative circuit including a frequency resonating unit capable of changing a resonance frequency, and a quenching circuit capable of changing a quenching oscillation frequency for changing reception sensitivity characteristics, and detecting an output level of the super regenerative circuit The level detection circuit to perform, during the reception standby, the quenching oscillation frequency of the quenching circuit is adjusted so that the reception sensitivity characteristic of the super-regeneration circuit has a predetermined wideband characteristic, and at the start of reception, the level detection circuit detects The resonance frequency of the frequency resonance unit is adjusted so that the output level becomes a constant value, and then, the quenching oscillation frequency of the quenching circuit is adjusted so that the reception sensitivity characteristic becomes a predetermined narrow band characteristic. A control unit that adjusts a quenching oscillation frequency of the quenching circuit so as to be in the reception standby state. The features.

FIG. 2 is a block diagram of a super-regenerative receiver provided with the above-mentioned super-regenerative receiving apparatus.

[0009] In FIG. 2, the super-reproduction receiver includes a super-reproduction circuit 3, a level detector 8, and a control unit 9. The super-regeneration circuit 3 differs from the conventional super-regeneration circuit shown in FIG. 1 in that the resonance frequency of the high-frequency oscillator 5 can be varied and the quench oscillation frequency of the quench oscillator 6 is variable. It is a point that can be done. The level detector 8 detects the level of the output of the super-regeneration circuit, which is the output of the low-pass filter 7,
This result is passed to the control unit 9. The control unit 9 operates as follows.

(1) During standby for reception The quench oscillation frequency of the quench oscillator 6 is adjusted so that the reception sensitivity characteristic of the super-regeneration circuit 3 has a predetermined wideband characteristic.

(2) At the start of reception The resonance frequency of the frequency resonance section is adjusted so that the output level detected by the level detector 8 becomes a constant value, and thereafter, the quenching is performed so that the reception sensitivity characteristic has a predetermined narrow band characteristic. Adjust the tuning oscillation frequency.

(3) At the end of reception The reception end signal is received from a data processing circuit (not shown), and the quenching oscillation frequency is adjusted so as to obtain the reception sensitivity characteristic at the time of standby for reception.

FIGS. 3A to 3E are sensitivity characteristic diagrams for explaining the operation of the control section.

In the standby state of (1), the quenching oscillation frequency is adjusted so as to obtain a wide band characteristic as shown in FIG. Note that f0 indicates a tuning frequency.

In this state, even if the tuning frequency f0 deviates from the initial set value due to a change in the temperature of the element or the like, the sensitivity does not suddenly decrease. Next, if the tuning frequency f0 shifts like f0 'in this way, the reception level also drops because the sensitivity is lowered when reception is actually started. Of course, at this time, the output level of the super-regeneration circuit also decreases. FIG. 3B shows the characteristic at this time. This lowering of the level is detected by the level detector 8 and the state is notified to the control unit 9. The control unit 9 includes the level detector 8
So that the output level detected at becomes a constant value, that is,
Usually, the resonance frequency is adjusted so that the level becomes the maximum value. As a result, the tuning frequency is corrected, and the reception sensitivity characteristic of the super-reproduction circuit is corrected as shown in FIG. Immediately thereafter, as shown in FIG. 3D, the reception sensitivity characteristic is set to a narrow band characteristic. The narrow band characteristic is obtained by adjusting the quench oscillation frequency. The frequency adjustment amount is determined so that the S / N becomes an optimum value. Actual data is received under this narrow band characteristic. When the data processing unit detects the end of the data, a reception end signal is passed to the control unit 9.

When receiving this signal, the control unit 9 determines that the reception has ended, and adjusts the quenching oscillation frequency so as to adjust to the original wideband characteristic shown in FIG. 3A.

By the above operation, even if the characteristics of the elements in the super-reproduction circuit change with temperature or aging, signals can be received at a high S / N without deteriorating the receiving sensitivity.

In order to adjust the resonance frequency and the quenching oscillation frequency, a known varicap diode can be used. The reception end timing is
It can also be formed when the level detector 8 continuously detects a level state without a signal for a certain period of time.

[0019]

FIG. 4 is a circuit diagram of the super-regeneration circuit shown in FIG.

The high-frequency oscillator 5 shown in FIG. 2 is of a modified Colpitts type, and Q1, C2, L2, C6, C
7, C8, D2, C10, and C11. In this circuit, D2 is a varicap diode. When a control signal is output from the control unit 9 to the varicap diode D2, the resonance frequency is varied.
D2, C7, C8, C6, and L2 constitute a frequency resonance unit.

The quenching oscillator 6 shown in FIG.
Correspond to Q1, L1, R1, C3, C4, C5, D in FIG.
1 and a self-excited type. Of these, D1
Is a varicap diode, and a control signal is applied from the control unit 9 to the varicap diode D1, whereby the quench oscillation frequency is varied.

FIG. 5 shows a circuit example of a super regenerating circuit in which a quenching oscillator is separately excited. In the super-regenerative circuit using the separately excited quench oscillator, the separately excited quench oscillation frequency is directly input to the base of the transistor Q1. Also in this case, the control signal input to the varicap diode D1 is controlled by the control signal from the control unit 9, and the quench oscillation frequency is adjusted.

In the super reproducing apparatus using the super reproducing circuit shown in FIGS. 4 and 5, the terminal voltage of the varicap diode D1 is controlled by the control signal from the control section 9 in the standby state for reception, and the capacitor value is varied. You. At this time,
The quenching oscillation frequency is set so that the reception sensitivity characteristic of the super-regeneration circuit has a predetermined broadband characteristic as shown in FIG.
That is, the capacitor value is adjusted. When the reception sensitivity becomes wide, even if the reception carrier frequency and the tuning frequency are relatively shifted, the level detection by the level detector 8 can be easily performed. If the tuning frequency f0 deviates from the reception carrier frequency f when the reception is actually started, the level detector 8 detects a decrease in the reception level corresponding to the deviation. , So that the output level detected by the level detector 8 becomes a constant value (usually the maximum value).
The terminal voltage of the varicap diode D2 is controlled.
At this time, the tuning frequency and the received carrier frequency match. Further, immediately after this, the terminal voltage of the varicap diode D1 is controlled to narrow the reception sensitivity characteristic. The degree of band narrowing is appropriately determined by adjustment so that the S / N becomes an optimum state. As a result, FIG.
The reception sensitivity characteristic is as shown in FIG. In this state,
The signal is detected by the super-regeneration circuit and output to the subsequent stage. When the reception of the signal is completed, the terminal voltage of the varicap diode D1 is controlled again, and the reception sensitivity characteristic is adjusted to have a broadband characteristic as shown in FIG.

In order to stabilize the operation, the terminal voltage of the varicap diode D2 may be controlled only when the output level detected by the level detector 8 falls below a predetermined value (for example, 10 dBm) from the initial setting sensitivity. Good. The signal reception end timing can be set when the signal processing unit detects the end of the signal. However, when the output level detected by the level detector 8 continuously detects a signal-free level for a certain period of time. Can also be set. This determination may be made by the control unit 9 or by the level detector 8.

The super regenerative receiver shown in FIG. 2 can demodulate FM waves as well as AM waves. That is, since the frequency-detection output characteristic of the super-regeneration circuit has a parabolic characteristic as shown in FIG. 6A, it is also possible to demodulate the FM wave by using a linear part as shown in the figure. It is. FIG. 1B shows an FM wave demodulation method using a normal S-shaped characteristic. In addition, as shown in FIG. 7, a super-heterodan type super-recovery detection circuit can be configured by arranging a frequency conversion unit and an intermediate frequency amplifying unit at a stage preceding the super-regeneration circuit.

The super-reproduction receiver described above can be applied to a remote control receiver.

FIG. 8 is a diagram showing an example of use for a wireless door lock remote controller for locking / unlocking a door of a passenger car. The remote control transmitter has a switch for locking and unlocking as shown in FIG. 2B, and the control unit receives the switch signal and controls the I / O of the remote control transmitter itself.
The D code and the command code for the switch signal are combined, modulated, and transmitted. In the receiver, FIG.
As shown in (1), the signal received by the receiving antenna is detected by a super-regeneration circuit, restored to a code before modulation, and passed to the control unit.
Here, the command code and the ID code are extracted, collated with those read from the storage device, and if they match, the command for the command code is executed. That is, the door is unlocked or locked via the actuator.

In addition to the above, the super-reproduction receiving device may be any of a remote control system using a remote control as shown in FIG. 9, a wireless garage opener as shown in FIG. 10, or a wireless engine starter as shown in FIG. It can be applied to remote control systems.

[0029]

According to the present invention, high sensitivity and high S / N ratio can be obtained even if the tuning frequency shifts due to temperature change or aging, or if the carrier frequency on the transmitting side drifts. A signal can be received, and communication quality can be maintained and reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram of a super regenerative receiver including a conventional super regenerative receiving device.

FIG. 2 is a block diagram of a super-regenerative receiver having the super-regenerative receiving apparatus according to the present invention;

FIGS. 3A to 3E are diagrams showing reception sensitivity characteristics for explaining the operation of the super-reproduction receiver according to the present invention;

FIG. 4 is a circuit example of a super-regeneration circuit according to an embodiment of the present invention;

FIG. 5 is another circuit example of the super regenerating circuit.

6A and 6B are frequency-detection output characteristics of a super-regeneration circuit and S-shaped characteristics of FM demodulation.

FIG. 7 is a block diagram of a superheterodyne type super-regeneration detection circuit

8A to 8C are configuration diagrams of a wireless door lock remote control system.

FIG. 9 is a configuration diagram of a remote control system.

FIG. 10 is a configuration diagram of a wireless garage opener system.

FIG. 11 is a configuration diagram of a wireless engine starter system.

Claims (9)

[Claims] 1. A super-regeneration circuit comprising: a frequency resonance section capable of varying a resonance frequency; and a quenching circuit capable of varying a quenching oscillation frequency for changing reception sensitivity characteristics. And a level detection circuit for detecting the output level of the quenching oscillation frequency of the quenching circuit so that the reception sensitivity characteristic of the super-regeneration circuit has a predetermined wideband characteristic during reception standby. The resonance frequency of the frequency resonance unit is adjusted so that the output level detected by the detection circuit becomes a constant value, and thereafter, the quenching oscillation frequency of the quenching circuit is adjusted so that the reception sensitivity characteristic has a predetermined narrow band characteristic. A control unit that adjusts a quenching oscillation frequency of the quenching circuit so as to be in the reception standby state at the end of reception; Provided to become super regenerative receiver. 2. The frequency resonance section includes a first varicap diode for varying a resonance frequency, the quenching circuit includes a second varicap diode for varying a quench oscillation frequency, The control unit is configured to change the resonance frequency and the quenching oscillation frequency by changing the first and second frequencies.
2. The super-regenerative receiving apparatus according to claim 1, wherein an applied voltage to said varicap diode is controlled. 3. The super-reproduction receiving apparatus according to claim 1, wherein said control section detects the end of reception by a signal end signal from a signal processing section for processing a received signal. 4. The super-reproduction receiving apparatus according to claim 1, wherein said control unit detects reception end when said level detection circuit continuously detects a corresponding level without signal for a predetermined time. 5. The super regenerative receiving apparatus according to claim 1, further comprising a frequency converter and an intermediate frequency amplifier provided at a stage preceding said super regenerating circuit. 6. The quench oscillation frequency is adjusted so that the resonance frequency and the quench oscillation frequency of the super-regeneration circuit are variable, and the reception sensitivity characteristic has a predetermined wide-band characteristic during reception standby. The resonance frequency is adjusted so that the output level of the circuit becomes a constant value, and then the quenching oscillation frequency is adjusted so that the reception sensitivity characteristic becomes a predetermined narrow band characteristic. Wherein the quenching oscillation frequency is adjusted so as to obtain the reception sensitivity characteristic described above. 7. A remote control receiver using the super-reproduction receiver according to claim 1. 8. The remote control receiver according to claim 7, further comprising an actuator for locking / unlocking the door based on the reception output signal. 9. A remote control system comprising a remote control transmitter and the remote control receiver according to claim 7.