JPH04359176A - Beacon transmitter - Google Patents

Abstract

PURPOSE:To provide a beacon transmitter with a long transmitting time by reducing the power consumption. CONSTITUTION:A transmission section 1 generates a beacon transmission signal and transmits it from an antenna 5. A reception section 2 detects the beacon transmission signal from another beacon transmitter inputted from the antenna 5. A control circuit 3b controls the operations of the transmission section 1 and the reception section 2 so that transmission and reception are performed in turn by switching pulse signals from a switching circuit 3a, and it controls the transmission section 1 not to perform transmission during the next transmitting period if a transmission signal from another beacon transmitter is received during reception. No beacon transmission is performed from this beacon transmitter while the beacon transmission from the other beacon transmitter is performed, thus the power consumption can be reduced, and the transmitting period can be extended.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a beacon transmitter,
In particular, the present invention relates to a beacon transmitter that is driven by a battery and outputs amplitude-modulated radio waves by repeatedly sweeping a carrier wave with a modulation signal.

[0002] Beacon transmitters are used as personal portable life-saving radio equipment, etc., and are carried by pilots and crew members of aircrafts, etc. In the event of an emergency, the pilot and crew operate the beacon transmitter and emit radio waves from the beacon transmitter. By receiving radio waves from the beacon transmitter at a ground station, etc., the distress point can be recognized and search operations can be facilitated.

[0003] Such beacon transmitters are required to transmit radio waves for long periods of time in preparation for long-term search activities.

0004

2. Description of the Related Art FIG. 4 shows a block diagram of a conventional beacon transmitter. In the figure, 12 is a modulation circuit, to which a carrier wave is supplied from an oscillator 6 using a crystal resonator 9, and the output of a sawtooth wave generation circuit 7 is converted to V/F (voltage/
frequency) converter 8, and a modulated signal obtained by voltage-frequency conversion is supplied. At this time, the modulation signal becomes a signal whose frequency gradually changes according to the voltage level of the sawtooth wave signal output from the sawtooth wave generation circuit 7.

The modulation circuit 12 converts the carrier wave from the oscillator 6 into V
Amplitude modulation is performed using the modulation signal from the /F converter 8. The output signal of the modulation circuit 12 was transmitted from the antenna 10. Power was supplied to each circuit from a battery 11.

[0006]

[Problem to be Solved by the Invention] However, since conventional beacon transmitters were constantly transmitting, for example, if multiple people were in distress at the same time, multiple beacon transmitters would start transmitting at the same time. , if the victims were rescued one by one, the lifespan of battery 11 would be 24.
If the first person was rescued 23 hours after the accident, there would be only one hour to rescue the remaining victims by relying on the radio waves from the beacon transmitter. There were some problems, such as making it difficult.

The present invention has been made in view of the above points, and an object of the present invention is to provide a beacon transmitter that lengthens transmission time by reducing power consumption.

[0008]

SUMMARY OF THE INVENTION FIG. 1 shows a block diagram of the principle of the present invention. The transmitter 1 generates a transmission signal by amplitude modulating a carrier wave using a pulse modulation signal whose frequency gradually changes. The receiving unit 2 receives transmission signals from other beacon transmitters, and the control unit 3 controls the transmitting unit 1 and the receiving unit 2 to operate alternately for each predetermined period, If a transmission signal from the other beacon transmitter is received when the reception unit 2 is in operation, the transmission unit and the reception unit are controlled to stop the operation of the transmission unit during the next operation period of the transmission unit. do.

[0009]

[Operation] The beacon transmitter is equipped with a receiving section and a control section and transmits and receives beacon waves alternately.If a beacon transmission signal from another beam is received during reception operation, transmission will be stopped during the next transmission period and If there is no beacon transmission from the crosspiece, the beacon will be transmitted.

[0010] Therefore, since transmission is stopped while another crosspiece is transmitting, battery consumption can be reduced.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 shows a block diagram of one embodiment of the present invention. In the figure, 1 indicates a transmitter. Transmitter 1 is crystal oscillator 1
oscillator 1b with a, sawtooth wave generation circuit 1c, V/F
It consists of a converter 1d and a modulation circuit 1e. The oscillator 1b outputs a carrier wave of a constant frequency predetermined by regulations as shown in FIG. 2(C), and is supplied to the modulation circuit 1e.

The sawtooth wave generating circuit 1c generates a sawtooth wave signal as shown in FIG. 3(A), and supplies it to the V/F converter 1d. The V/F converter 1d generates a signal whose frequency changes according to the voltage level of the sawtooth wave signal output from the sawtooth wave generation circuit 1c as shown in FIG. Outputs a detection signal according to the detection signal.

Reference numeral 3 indicates a control section. The control section 3 is a switching circuit 3
a, and a control circuit 3b. A sawtooth wave signal is supplied to the switching circuit 3a from the sawtooth wave generation circuit 1c. The switching circuit 3a detects the rise of the sawtooth wave signal from the sawtooth wave generation circuit 1c, and generates a switching pulse signal that becomes low for a certain period of time at the rise of the sawtooth wave signal, as shown in FIG. 3(D). and supplies it to the control circuit 3b. Control circuit 3
b is supplied with a switching pulse signal from the switching circuit 3a and a reception detection signal from the reception detection circuit 2c. The control circuit 3b is connected to the modulation circuit 1e and the high frequency amplifier 2a, and supplies the modulation circuit 1e and the high frequency amplifier 2a according to the switching pulse signal and the reception detection signal. Modulation circuit 1e is oscillator 1b
The carrier wave from the V/F converter 1d is amplitude-modulated by the modulation signal output from the V/F converter 1d and output. The output of the modulation circuit 1e is supplied to the antenna 5 and transmitted.

[0014] 2 indicates a receiving section. The receiving section 2 includes a high frequency amplifier 2a, an intermediate frequency amplifier 2b, and a reception detection circuit 2c. The high frequency amplifier 2a amplifies and outputs the high frequency signal supplied from the antenna 5. The output of high frequency amplifier 2a is supplied to intermediate wave amplifier 2b. Intermediate frequency amplifier 2b
amplifies and outputs intermediate frequency band signals. The output signal of the intermediate frequency amplifier 2b is supplied to the reception detection circuit 2c. The reception detection circuit 2c detects transmission signals from other beacon transmitters and controls the operation of the received transmission signal high frequency amplifier 2a. The control circuit 3b controls the modulation circuit 1e during the period when the switching pulse signal of the switching circuit 3a shown in FIG. The beacon transmission signal is controlled so that the receiving section 2 receives the beacon transmission signal. Control circuit 3
When the receiving unit 2 receives a beacon transmission signal from another beacon transmitter during the period when the switching pulse signal is low, it controls the modulation circuit 1e to change the beacon transmission from this device to the next low switching pulse signal. Suspended for a period of time.

Therefore, when a beacon transmission signal from another beacon transmitter is detected in period T as shown in FIG. 3, no output beacon transmission signal is transmitted as shown in FIG. During a period in which no transmission signals from other beacon transmitters are being received, the device will transmit a beacon transmission signal as shown in FIG. 3(E). In this way, switching between transmission and reception is performed according to the switching pulse signal of the switching circuit 3a, and when a beacon transmission signal is received from another beacon transmitter during the reception period, the beacon transmission signal from this device is transmitted during the next transmission period. Since transmission is configured to be stopped, power consumption can be reduced compared to when multiple beacon transmitters are constantly transmitting, resulting in less battery consumption. Therefore, the time during which the beacon transmission signal can be transmitted can be extended.

[0016]

[Effects of the Invention] As described above, according to the present invention, since transmission is stopped when another beacon transmitter is transmitting, battery consumption is reduced compared to when transmitting all the time. Therefore, it has the advantage of being able to perform transmission for a longer time when there are transmissions from multiple beacon transmitters.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the principle of the present invention.

FIG. 2 is a block diagram of one embodiment of the invention.

FIG. 3 is a diagram for explaining the operation of an embodiment of the present invention.

FIG. 4 is a block diagram of a conventional example.

[Explanation of symbols] 1 Transmission section 2 Receiving section 3 Control section 4 Battery 5 Antenna

Claims (1)

[Claims] [Claim 1] A transmission unit (1) transmits a transmission signal in which a carrier wave is amplitude-modulated by a pulse-like modulation signal whose frequency gradually changes.
In a beacon transmitter that generates a transmission signal and transmits the transmission signal, a reception section (2) that receives a transmission signal from another beacon transmitter, and a transmission section (1) and a reception section (2), respectively. When the receiving section (2) receives a transmission signal from the other beacon transmitter while the receiving section (2) is operating, the next transmitting section (1) During the operation period, the transmitting section (1) and the receiving section (2) are operated so that the operation of the transmitting section (1) is stopped.
A beacon transmitter characterized by having a control section (3) that controls.