JPH0779302B2 - Pulse transceiver - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates generally to wireless systems employing pulse repeaters, and more particularly to pulse communication systems utilizing pulse repeaters capable of operating at more than one frequency.

[0002]

2. Description of the Related Art A pulse communication system employing a pulse repeater is disclosed in US Pat. No. 3,825,829 granted to the inventor of the present invention.
(Corresponding Japanese application: JP-A-49-111502). This prior invention discloses a system for transmitting pulses through an installed field of pulse repeaters. That is, there is disclosed a system in which pulse signals are sequentially transmitted through a pulse repeater that receives and retransmits pulse signals in a region where pulse signals cannot be directly transmitted due to the presence of an obstacle or the like. After transmitting the pulse, each repeater suspends operation for a certain time interval. By interrupting the operation of the pulse repeater so that another pulse cannot be repeated, the system is prevented from self-oscillating. The bit rate available in prior art systems is limited by this break time interval, which is determined by the maximum propagation delay of the pulse in any particular system implementation.

[0003]

This pulse communication system, which employs a pulse repeater, has the ability to repeat a pulse using multiple frequencies, thereby allowing transmission as compared to a single frequency system. Increases the pulse bit rate and system throughput.

The pulse communication system has a plurality of pulse repeaters and transmits and receives pulse signals in a chain reaction. Each repeater has frequency control means and selects one of a sequence of transmit and receive frequencies. After receiving one pulse, the frequency control means changes one of the transmit frequency and the receive frequency to receive and transmit the next pulse at another frequency.

According to one aspect of the invention, the pulse repeater comprises receiving means for receiving the pulse signal. The detecting means is connected to the receiving means for detecting the presence of the pulse signal. The transmitting means responds to the detecting means and transmits the pulse signal based on the detection of the pulse signal. The frequency control means controls the operating frequencies of the receiving means and the transmitting means. The receiving means waits to receive the pulse signal of the frequency selected by the frequency control means. When the detection means detects the pulse signal, the transmission means responds to the detection of the pulse signal by the detection means and transmits the pulse signal at the frequency selected by the frequency control means. When the transmitting means transmits the pulse signal, the frequency controlling means changes the receiving frequency of the receiving means, and waits for the reception of the next pulse signal at a frequency different from the transmitting frequency.

As another aspect of the invention, a pulse transceiver is provided for receiving and transmitting pulse signals. The frequency control means changes the transmission frequency after transmitting each pulse, and changes the reception frequency after receiving each pulse.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic operation of a wireless system using a pulse repeater including operations of a repeater and a portable device (transceiver) is described in U.S. Pat. No. 3,825,829 and its disclosure. The contents are included herein by reference in such a way that the entire contents are made clear. The operation of the system of the present invention, which repeats the transmission of pulses at multiple frequencies, is described below, but in order to increase the bit rate and throughput of the system, the pulses are composed of a series or series of pulses .

Referring to the drawings and referring first to FIG. 1, a repeater 10 has an antenna 11, and this antenna 11 is a transmission / reception switch for switching the antenna between a receiver section and a transmitter section of the repeater. RF switch 1 that functions as
It can be seen that it is connected to 2. RF switch 1
The received output of L.2 is connected to a pulse receiver 13 constituted by a receiving means, which is a series of local oscillators, namely L.L.
0. # 1, L.L. 0. # 2 and L.L. 0. It has a frequency selectively controlled by #N. Each local oscillator 14-16 supplies a different frequency to the pulse receiver 13 in order to select the reception frequency. The number of local oscillators used depends on the number of operating frequencies of the repeater 10 and includes at least two local oscillators because it operates at at least two frequencies. Frequency synthesizers known in the art may be used as an alternative means of providing the local oscillator signal without the use of an individual local oscillator.

The output of the pulse receiver 13 is applied to a decision amplifier 20 constituted by detection means, which is used to determine when a pulse has been received.
When the decision amplifier 20 receives the pulse shown as the high level signal in FIG. 7A, the delay amplifier 21, the frequency controller 22, the pulse generator 23 and the key input circuit 2 are received.
An output pulse is supplied to operate the pulse generator 4. The delay oscillator 21 supplies an output signal for giving a blank to the pulse receiver 13 as shown in FIG. 7D while the pulse is being transmitted. The frequency controller 22 constituted by the frequency control means is used for selecting the local oscillators 14 to 16 which determine the reception frequency of the repeater.
The pulse generator 23 supplies the pulse signal shown in FIG. 7 (E) for transmission. The key input circuit 24 is the relay 10
It is used to operate the RF switch 12 that switches the antenna 11 to the transmitting section of the above, and to operate the pulse transmitter 25 configured by the transmitting means to transmit a pulse to the antenna 11 via the switch 12.

The pulse output of the pulse generator 23 is also supplied to the inverter 26 connected to the frequency controller 22 for operating the frequency controller at the falling edge of the pulse. Transmit oscillator T. 0. # 1, T.W. 0. # 2, and T.S. 0. #N, 30 to 32 are connected to the frequency controller 22 and the pulse transmitter 25, respectively. Transmit oscillators 30-32 are used to determine the transmit frequency of the transmit pulse. The transmission oscillators 30 to 32 are the local oscillator 1
A transmission frequency corresponding to the reception frequency determined in 4 to 16 is supplied. The number of transmission oscillators is determined by the number of operating frequencies of the repeater 10. If desired, a frequency synthesizer or other conventional means may be used to oscillate the transmit oscillator frequency.

An example of operation is shown next. Pulse receiver
13 is the first frequency set by the local oscillator 14
(F₁) Receives the first pulse. The decision amplifier 20 is
It is determined that one pulse has been received, and the pulse transmitter 25
Pulse signal for transmission (frequency f ₁) Pulse
It is sent to the generator 23. Reception frequency of pulse receiver 13
Is (by the local oscillator 15) then the frequency f₂Set up
And receive the next pulse at that frequency. Or
, The repeater has frequency f₂Relay that pulse at
Frequency to be defined (frequency f_NSwitch to)
Be done. Therefore, the repeater 10 receives the power of each pulse received.
Relay at the lus frequency and then advance for the next pulse
Switch to the specified frequency. Repeater 10 is the Nth pulse
The above procedure is repeated until the packet is received and transmitted. That
After that, the repeater 10 has a frequency f₁To frequency f_NNext cyclist
Start. Therefore, the receive and transmit frequencies are
It is changed for each received pulse. The reception frequency of each pulse is
To the frequency set by the local oscillators 14 to 16.
Therefore, the frequency of each transmission pulse is set to the transmission oscillator 30 to 3
Corresponds to the frequency set by 2.

Referring now to FIG. 2, the circuitry of the frequency controller 22 when the repeater 10 operates at two frequencies is shown. For two operating frequencies, the local oscillator 14
It can be seen that only and 15 and transmit oscillators 30 and 31 are used. The output of the decision amplifier 20 is connected to the C input (clock) of a D flip-flop 35, which has its D input connected to the Q-bar output for toggle operations. The Q output of flip-flop 35 is connected to local oscillator 14 and the Q output is connected to local oscillator 15. The Q and Q bar outputs of flip-flop 35 are shown by the waveforms in FIGS. 7B and 7C, respectively. These waveforms also show the operating states of the two local oscillators 14 and 15. The local oscillator 14 or 15 associated with the high level output of the flip-flop 35 is operated to determine the reception frequency of the pulse receiver 13.

The Q output of flip-flop 35 has a second
Also connected to the D input of a D flip-flop 36, which has a Q output connected to the transmit oscillator 30 and a Q bar output connected to the transmit oscillator 31. The clock input of the D flip-flop 36 is passed through the inverter 26 and the pulse generator 23.
Connected to the output of. The waveforms of the Q and Q bar outputs of flip-flop 36 are shown in FIGS. 7F and 7G, respectively. These waveforms also show the operating states of the two transmit oscillators 30 and 31.

It can be seen that the outputs of flip-flops 35 and 36 are the same until the pulse is received by pulse receiver 13, as shown by the output pulse from decision amplifier 20. That is, since both Q outputs are the same and both Q bar outputs are the same,
As a result, the pulse receiver 13 and the pulse transmitter 25 are at the same frequency. When a pulse is received, the output pulse from decision amplifier 20 is applied to the C input of flip-flop 35, which toggles flip-flop 35.
That is, the output is inverted. Flip-flop 36 is unaffected because it is not clocked at this time. The pulse generator 23 first oscillates a pulse to be transmitted. The falling edge of the pulse from pulse generator 23 appears as the rising edge from inverter 26, clocking flip-flop 36 and flipping its output.
It is set to the same state as the output of the flop 35.

While the frequency control circuit of FIG. 2 is particularly useful for repeaters having two frequency pulses, three or more operating frequencies do not utilize different equipment as illustrated in FIG. must not. The frequency controller of FIG. 3 comprises a shift register 40 having a number of outputs equal to N corresponding to the number of operating frequencies of the repeater 10. The single high level output is shifted from output to output through the shift register, resulting in the high level output being shifted to the next successive output for each clock pulse from decision amplifier 20. The first output of shift register 40 is
Connected to local oscillator 14, the second output is connected to local oscillator 2, and the Nth consecutive output is connected to an associated local oscillator, such as local oscillator 16.

Each output of shift register 40 is also connected to the D input of the associated D flip-flop. In this case, flip-flop 41 is connected to output 1,
Flip-flop 42 is connected to output 2 and flip-flop 43 is connected to output N. The Q outputs of flip-flops 41-43 are connected to the associated transmit oscillators 30-32, respectively. Flip-flop 41-
The clock inputs of 43 are tied together and the inverter 2
6 outputs.

When a pulse is received, the output of decision amplifier 20 goes high, clocking the shift register, shifting the high level output by one position, changing the selected receiver local oscillator, Therefore, the reception frequency is changed. The selected transmit oscillator does not change until after the transmit pulse has been sent, because all clock inputs of D flip-flops 41-43 are inverter 26.
This is because it is controlled by the output of the pulse oscillator 23 via. Once flip-flops 41-43 have been clocked, the associated set of local and transmit oscillators is again selected, thereby selecting the same receive and transmit frequencies for repeater 10.

The pulse transceiver 50 is illustrated in FIG. The pulse transceiver 50 includes a number of components that are equivalent or identical to those of the pulse repeater 10. Antenna 5
1 can be selectively switched between the transmitter section and the receiver section of the transceiver 50 via the RF switch 52. The signal received from the antenna 51 is supplied to a pulse receiver 53 configured as a receiving means, and its output is connected to a decision amplifier 54 configured as a detecting means. The output of the decision amplifier 54 is connected to a frequency controller 55 and a demodulator 59 configured as frequency control means. The input of the clock recovery circuit 56 is connected to the output of the pulse receiver 53, and the output is connected to the demodulator 59.

The output of the demodulator 59 is the amplifier 57, the selectively invoked squelch circuit 60 and the AND gate 6.
1 is supplied. The other input of the AND gate 61 is connected to the output of the squelch circuit 60 which is selectively called. The output 62 of the AND gate 61 is the data output line of the transceiver 50. The audio output of the transceiver 50 is provided by a speaker 58 connected to an audio amplifier 57.

The data transmitted by transceiver 50 can be provided from microphone 66 to pulse generator 70 via data source 65 or modulator 67. The output of the pulse generator 70 is connected to a pulse transmitter 71 configured as a transmission means, and the pulse transmitter 7
1 is connected to the RF switch 52. Key input circuit 73
Is operated by a talk push button switch (not shown). The key input circuit 73 operates the RF switch 52, the pulse transmitter 71, and the clock circuit 74. The output of the clock 74 is supplied to the modulator 67 and used to convert the sound from the microphone 66 into a pulse signal.

The output of the pulse generator 70 is also supplied to the frequency controller 55 via the inverter 80. Like the repeater 10, the output of the frequency controller 55 is also connected to the local oscillators 1, 2 and N, 81-83, respectively.
Connected to transmitter oscillator numbers 1, 2 and N, 84-86, respectively. Frequency controller 55 controls the selection of both receiver and transmitter oscillators to control the receive and transmit frequencies of the transceiver.

FIG. 5 shows the circuitry of the frequency controller 55 for operation at two frequencies. The frequency controller has one OR gate 90, which has one input connected to the output of the decision amplifier 54.
The output of the inverter 80 is connected to the one-shot circuit 91 and outputs a single pulse for each rising pulse supplied to its input. The output is the OR gate 90.
Connected to the other input of. The output of the OR gate 90 is
Connected to the C input of D flip-flop 92. The D flip-flop is configured to bring its Q-bar output back to its D input and toggle. The Q output of flip-flop 92 operates both local oscillator 81 and transmit oscillator 84. The Q-bar output of flip-flop 92 operates both local oscillator 82 and transmit oscillator 85.

Upon receipt of a pulse during the receive period, decision amplifier 54 provides a pulse to OR gate 90 which clocks flip-flop 92 to perform a toggle operation and its output to switch the receive frequency. Switch. During the transmission period, at the falling edge of each pulse from pulse generator 70, inverter 80 supplies the rising edge to one shot 91, which in turn supplies a pulse to OR gate 90, which causes flip-flop 92. To change the operating frequency of the transceiver.

For operation at more than two frequencies, frequency controller 55 must utilize different circuits.
FIG. 6 shows a circuit operable at multiplex or N frequencies, where N is an integer greater than one. As shown,
The output from the decision amplifier 54 is supplied to one of the inputs of the OR gate. The output of the inverter 80 is connected to the other input of the OR gate 93 via the one-shot circuit 94. The output of the OR gate 93 is the shift register 95.
Clock input C. Shift of repeater 10
Like register 40, shift register 95 controls N transmit oscillators and N receive oscillators,
Used to shift a single high level output. Its first output is connected to local oscillator 81 and transmit oscillator 84, its second output is connected to local oscillator 82 and transmit oscillator 85, and the Nth output is local oscillator 8
3 and the transmission oscillator 86.

In operation, when the first output of shift register 95 is high and a clock pulse is received, the first output goes low and the second output goes high. The high output of shift register 95 shifts one position for each successive clock pulse received and the falling edge of every transmitted pulse. The N output of shift register 95 is returned to its input to recycle a single high level output through the shift register. The operating frequency of the transceiver 50 is shifted after each pulse is transmitted or after each pulse is received.

Referring to FIG. 8, a representative application of pulse repeater 10 and pulse transceiver 50 is shown. As shown, a plurality of pulse repeaters 10 are distributed to cover the service area of the system. Individual transceivers 50 are located at desired locations so that information can be sent and received within the system.

In operation, one of the transceivers 50 introduces a pulse into the system for the first frequency. This pulse is picked up by one or more repeaters 10 in the vicinity, and repeater 1
Those of the same frequency are retransmitted by the repeater 10 for transmission through the 0 field. After the transceiver 50 transmits for the pulse, the transceiver 50 repeats the pulse and then switches to the next frequency, as each repeater 10 does. Transceiver 50 may introduce a second pulse into the system for a second frequency while the first pulse is still being repeated via another repeater 10 that is remote from transceiver 50. it can. The use of multiple frequencies will be appreciated in that it allows multiple pulses to be transmitted simultaneously in the system. For example,
If three frequencies are used, the repeater located furthest from the first transceiver 50 will be the first one with respect to the first frequency while the repeater in the middle repeats the pulse at the second frequency. The pulses can be repeated and transmitter 50 and repeater 10 in the vicinity can operate at a third frequency.

Although the present embodiment is constructed as a wireless system, it is also possible to use ultrasonic, infrared or light pulses.

[0029]

As described above, the present system is substantially advantageous in terms of processing capacity with respect to a system using a single frequency.

[Brief description of drawings]

FIG. 1 is a functional block diagram of a repeater used in a system according to the present invention.

2 is a schematic electrical diagram of a frequency controller used in the repeater operating at the two frequencies shown in FIG. 1. FIG.

3 is a schematic electrical diagram of a frequency controller used in multi-frequency operation in the pulse repeater shown in FIG.

FIG. 4 is a block diagram of a transceiver used in a communication system according to the present invention.

5 is a schematic electrical diagram of a frequency controller used in the operation of two frequencies in the repeater shown in FIG.

6 is a schematic electrical diagram of a frequency controller used in the transceiver shown in FIG. 4 for use in multi-frequency operation.

7 shows various timing charts used in the repeater shown in FIG. 1 for use in dual frequency operation.

FIG. 8 is a block diagram of an exemplary wireless system according to the present invention.

[Explanation of symbols]

1,2,14,15,16,81,82,83 Local oscillator 10 Interrupter 11,51 Antenna 12,52 RF switch 13,53 Pulse receiver 20,54 Decision amplifier 21 Delay oscillator 22,55 Frequency control Device 23,70 Pulse generator 24,73 Key input circuit 25,71 Pulse transmitter 26,80 Inverter 30, 31, 32, 84, 85,86 Transmitting oscillator 35, 36, 41, 42, 43, 92 Flip Flop 40,95 Shift register 50 Pulse transmitter / receiver 56 Clock recovery circuit 57 Amplifier 58 Speaker 59 Demodulator 60 Squelch circuit 61 AND gate 62 Output 65 Data source 66 Microphone 67 Modulator 74 Clock circuit 90,93 OR gate 91,94 One shot circuit

Claims (3)

[Claims] 1. Receiving means for receiving a pulse signal; detecting means connected to the receiving means for detecting the presence of a pulse signal; connected to the detecting means and responding thereto; Transmitting means for transmitting a signal; and frequency control means for operatively selecting one of the operating frequency sequences of said receiving means and said transmitting means, said transmitting means for transmitting each received pulse at a received frequency A pulse repeater comprising: the frequency control means for selecting an operating frequency of the means and selecting a different reception frequency after receiving each pulse. 2. Receiving means for receiving a pulse signal; transmitting means for transmitting a pulse signal; and frequency control means for selecting an operating frequency of the receiving means and the transmitting means, the method comprising: A pulse transceiver, comprising: the frequency control means for changing the operating frequency of the receiving means, transmitting each pulse, and then changing the operating frequency of the transmitting means. 3. Receiving means for receiving pulse signals; transmitting means for transmitting pulse signals; and frequency control means for selecting operating frequencies of the receiving means and the transmitting means, after receiving each pulse, and A pulse transceiver comprising: the frequency control means for changing the operating frequencies of the transmitting means and the receiving means after transmitting each pulse.