KR0146683B1 - Pager - Google Patents

Abstract

The present invention relates to a radio call receiver having a frequency scan function, and more particularly, to a radio call receiver having a frequency scan function suitable for error-free reception of a signal transmitted in a user field.

The wireless call receiver having a frequency scan function provided by the present invention includes an antenna tuning unit for maximally passing a signal received through an antenna, a receiving unit for generating a digital signal from the received high frequency signal connected to the antenna tuning unit; And a controller configured to process an output of the receiver to notify a user of a call and generate a channel select signal for selecting a reception frequency having a high error efficiency by comparing with a pre-signal of another channel and responding to a channel select signal of the controller And a frequency synthesizer for generating and applying an oscillation frequency according to a selected channel to a receiver and at the same time applying a control frequency change control signal of the antenna driver.

Description

Radio call receiver with frequency scan

1 is a schematic block diagram of a radio call receiver system,

2 is a detailed block diagram of a conventional radio call receiver,

3 is a schematic block diagram of a radio call receiver according to an embodiment of the present invention;

4 is a detailed block diagram of a radio page receiver according to a preferred embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

41 antenna 42 receiver

43: antenna tuning section 44: frequency synthesis section

45: control unit 51: high frequency amplification circuit

52: mixed circuit 53: intermediate frequency amplifier circuit

54 demodulation part 55 switching circuit

56: constant voltage circuit 57: reference oscillator

58: reference divider 59: phase comparator

60: low pass filter 61: VCO

62: program counter 63: decoder

64: CPU 65: EEPROM

66: output device 67: first capacitor

68: second capacitor 69: third capacitor

70: fixed capacitance capacitor 71: variable capacitance diode

The present invention relates to a radio call receiver having a frequency scan function, and more particularly, to a radio call receiver having a frequency scan function suitable for error-free reception of a signal transmitted in a user field.

In general, a radio call receiver refers to a small radio call receiver for calling a person whose location is unclear or mobile through a paging system that is a land base station.

Such a radio call receiver typically uses a Post Office Committee Standard Association Group (POCSAG) code. The paging system assigns a unique code corresponding to the call address of each radio call receiver to call the radio call receiver. have. This unique code is a unique number assigned to each radio call receiver and is composed of 18 bits of magnetic address data and 3 bits of frame data included in an address codeword directly transmitted when the radio page receiver is called.

Therefore, the paging system propagates in the air to access the unique code corresponding to the dial information received from the subscriber and to call the corresponding radio call receiver. Then, the radio call receiver receives the unique code propagated in the air and compares it with its own pre-stored unique address. When the radio call receiver has the same address data, it recognizes that it is its own call and generates an alarm signal. The phone number will be displayed together.

Conventional radio page receivers have a fixed frequency to receive a transmission signal from a regular telephone in order to perform the above operation. When the transmission signal of the ordinary telephone comes through the antenna of the radio page receiver, the transmission signal is The intermediate frequency is converted to a fixed frequency of the receiver, and the intermediate frequency is generated, demodulated, and displayed on the LCD screen of the receiver.

Hereinafter, a conventional wireless pager will be described with reference to the drawings.

1 is a schematic block diagram of a radio call receiver system, and FIG. 2 is a detailed block diagram of a conventional radio call receiver.

Referring to FIG. 1, Pager system standard telephone network to connect the plurality of regular telephone ₍₁ 1, ... 1 _n) and the plurality of standard telephone _{(1 1, ... 1 n)} ( PSTN 12, radio call receiver 15, terminal 13 for inputting and outputting signals from PSTN 12, and for propagating signals from terminal 13 to radio call receiver 15. It consists of an antenna 14.

2 is a detailed block diagram of a conventional radio call receiver.

Referring to FIG. 2, a conventional radio call receiver includes an antenna 14 for applying a transmission signal of a general telephone, and a tuning stage 22 for tuning the signal of the antenna 14 to match a frequency set in the receiver. A high frequency amplifier (23) for amplifying the output signal of the tuning stage (22), a local oscillator (25) for generating a frequency for converting the received signal, and an output signal of the high frequency amplifier (23) and the local A mixer 24 for generating an intermediate frequency by mixing the output signal of the oscillator 25, amplifying the intermediate frequency that is the output of the mixer 24, 26, and demodulating for demodulating the signal of the intermediate frequency amplifier. A grandmother 27, a decoder 29 in which waveform signals shaped through the demodulator 27 are digitally processed and input, and a memory (EEPROM: Electric Erasible Programmable) for storing various kinds of information of a radio call receiver. Read Only Memory (28) A driver 30 for driving a signal of the decoder 29 and a speaker for notifying a user of the signal of the driver 30 when the data entered into the decoder 29 and the data stored in the EEPROM 28 match. An output device 31 including a light emitting diode (LED) and a motor, a central processing unit (CPU) 32 for receiving an output signal of the decoder 29, It consists of a liquid crystal display (LCD) 33 which displays a signal of the CPU 32.

In the conventional radio call receiver as described above, since the frequency input to the input terminal of the receiver is fixed, and the receiver itself can process only one frequency, it is manufactured and processed irrespective of the user and transmitted from the general telephone when the signal of the frequency is weakened. Signal is also weakened. As a result, a signal input to the receiver may be misprocessed to display incorrect data on the LCD screen or to miss the received signal itself.

Accordingly, an object of the present invention is to provide a radio call receiver having a frequency scan function suitable for receiving a signal transmitted in a user field without error.

In order to achieve the above object, a wireless call receiver having a frequency scan function provided by the present invention includes an antenna tuning unit for maximally passing a signal received through an antenna, and a high frequency signal connected to the antenna tuning unit. A receiving unit for generating a digital signal, a control unit for processing an output of the receiving unit to notify a user of a call and generating a channel selection signal for selecting a reception frequency having a high error efficiency by comparing with a pre-signal of another channel; The frequency synthesizer is configured to generate and apply an oscillation frequency according to the selection channel in response to the channel selection signal of the controller to the receiver and to simultaneously apply a tuning frequency change control signal of the antenna tuning unit.

Hereinafter, a radio call receiver having a frequency scan function of the present invention will be described with reference to the drawings.

3 is a schematic block diagram of a radio call receiver according to a preferred embodiment of the present invention, and FIG. 4 is a detailed block diagram of a radio call receiver according to a preferred embodiment of the present invention.

Referring to FIG. 3, the wireless call receiver according to the present invention includes an antenna 41 for applying a call signal of a general telephone and an antenna tuning unit 43 for maximally passing a signal received through the antenna 41. And a receiver 42 for generating a digital signal from the received high frequency signal connected to the antenna tuner 43, and processing the output of the receiver 42 to notify the user of a call and The control unit 45 generates a channel selection signal for selecting a reception frequency having a higher error efficiency than the pre-signal, and generates an oscillation frequency according to a selection channel in response to the channel selection signal of the control unit 45. And a frequency synthesizing section 44 for applying the tuning frequency change control signal of the antenna tuning section 43 at the same time.

Referring to FIG. 4, the receiver 42 includes a high frequency amplifying circuit 51 for amplifying a high frequency signal applied from the antenna tuning unit 42, and the high frequency signal and the frequency synthesizer 44. A mixing circuit 52 for generating an intermediate frequency by mixing oscillation frequencies according to a selected channel, and an intermediate frequency amplifier circuit 53 and an intermediate frequency amplifier circuit 53 for amplifying the intermediate frequency of the mixing circuit 52. A demodulator 54 for demodulating the output and outputting a digital signal; and receiving the constant voltage generated by the demodulator 54, the high frequency amplifying circuit 53, the mixing circuit 52, and the intermediate frequency amplifying circuit ( A constant voltage circuit 56 for supplying a stabilized operating voltage for the reference signal 53), and a tuning frequency change applied from the frequency synthesizer 44 to the antenna tuner 43 in accordance with the output of the constant voltage circuit 56. Switch to control the control signal The first and second condenser 67 and the second condenser 68 connected in parallel to the antenna 41, and the antenna tuning section 43, the first and second connected in parallel And a third capacitor 69 received in series with the capacitors 67 and 68. The second capacitor 68 includes a fixed capacitor 70 and a variable capacitor diode 71 to which a tuning frequency change control signal is applied. The tuning frequency is determined according to the tuning frequency change control signal, which is configured in a series connection configuration.

The controller 45 compares the EEPROM 65, which stores various states of the receiver, the stored signal of the EEPROM 65, and the digital signals of the receiver 42. A decoder 63 for outputting a digital signal of the receiver, receiving information about a pre-signal of another channel, comparing the received frequency signal with an error efficiency state and outputting a comparison result and the pre-signal of the other channel; An output device 66 for outputting a call signal to a user in response to the digital signal of the decoder 63; and the digital signal in response to the digital signal of the decoder 63 and the comparison result and the transposition signal of another channel. Informs the user through an indicator, and selects a signal having a high error efficiency in response to the comparison result and a pre-signal of another channel to display the high error efficiency. It consists of a central processing unit (CPU) 64 which sends a channel selection signal which can change a channel to a signal to the frequency synthesizing section 44.

In addition, the frequency synthesizer 44 includes a reference frequency oscillator 57 for generating a reference frequency, a reference divider 58 for dividing an output of the reference frequency oscillator 57, and the reference divider 58. A phase comparator 59 connected to and generating a phase difference, a low pass filter 60 for filtering the low pass output of the phase comparator 59, and the mixing circuit according to the voltage control signal filtered by the low pass filter 60; A voltage controlled oscillator (VCO) for generating an oscillation frequency applied to the antenna tuning unit 43 and the channel selection signal of the CPU 64 and the VCO 61; And a program counter 62 for comparing the outputs and applying the results to the phase comparator 59.

The radio call receiver having the scan function of the present invention configured as described above is tuned so that the signal passes through the antenna tuning circuit 43 to the maximum when the signal from the transmitter is received through the antenna 41 and the high frequency signal is transmitted. Input to the amplifier circuit 51. Since the signal input to the high frequency amplification circuit 51 is very weak, low noise amplification is output and input to the mixing circuit 52.

Then, the mixing circuit 52 simultaneously receives the received and amplified signal and the output signal of the VCO 61 and mixes the signals to produce an intermediate frequency. The intermediate frequency is inputted to the demodulator 54 which converts an analog signal into a digital signal through the intermediate frequency amplifying circuit 53. The demodulator 54 has a function for demodulating a signal and for supplying a constant voltage. The demodulator 54 forms the constant voltage circuit 56 together with a transistor, a resistor, and a capacitor to form the respective elements in the receiver 42. It will help to drive. The switching circuit 55 controls the output signal of the VCO 61 applied to the variable capacitance diode 71 of the antenna tuning unit 43 according to the input signal from the constant voltage circuit 56. Do it.

In addition, the decoder 63 compares the signal received from the demodulator 54 with the information embedded in the EEPRO M 63 and transmits the input information to the CPU 64 when it matches, and the EEPROM. 65 embeds various types of information of the receiver and transmits the information to the decoder 63 and the CPU 64. The CPU 64 receives the information received from the decoder 63 and the EEPROM 65. It serves to send to the output device (66).

In addition, when the decoder 63 receives the information about the pre-signal of another channel from the receiver 42, the decoder compares the information with the first information and sends the comparison result and the pre-signal to the CPU 64 together. The CPU 64 selects a signal having a high error efficiency in response to a comparison result and a pre-signal of another channel, and sends a channel selection signal to the frequency synthesizer 44 to change a channel to the signal having a high error efficiency. If it is determined that the error occurrence rates of the two signals are the same, information is first transmitted to the frequency synthesizer 44 so as to select a channel as it is.

When the CPU 64 compares the information of the pre-signal for each channel input to the receiver 43 in the same manner as described above and provides the program counter 62 with the information, the frequency synthesizer 44 ) Is then synthesized and determined according to the frequency. Therefore, the VCO 61 provides a predetermined frequency as a local oscillation signal of the receiver 42 and a voltage at which the variable capacitor diode 71 of the antenna tuning circuit 43 can be tuned to a predetermined frequency. Enter it. Therefore, when tuned to a predetermined frequency by the impedance change of the first, second and third capacitors in the antenna tuning circuit 43, the receiver 42 again processes the input signal through amplification, mixing and demodulation. Done.

Claims (5)

An antenna tuner for varying the tuning frequency using a variable capacitance diode according to a frequency change control signal while maximally passing a signal received through the antenna, and a local oscillation signal for transferring a high frequency signal connected to the antenna tuner. After converting the signal into an intermediate frequency signal, demodulating the intermediate frequency signal to generate a digital signal, and processing the output of the receiver to notify the user of the call and at the same time compare with the pre-signal of other channels, the error efficiency is high. The controller generates a channel selection signal for selecting a reception frequency, and generates and applies an oscillation frequency according to a selected channel by using a program counter, a phase comparator, and a voltage controlled oscillator in response to the channel selection signal of the controller. And at the same time, the variable capacitance diode Pager with a frequency scan function, characterized in that comprises a frequency synthesizing unit for applying a tuning frequency changing control signal. 2. The receiver of claim 1, wherein the receiver generates an intermediate frequency by mixing a high frequency amplifying circuit for amplifying a high frequency signal applied from the antenna tuning unit, and an oscillation frequency corresponding to a selected channel output from the high frequency signal and the frequency synthesizer. A mixed circuit, an intermediate frequency amplifier circuit for amplifying the intermediate frequency of the mixed circuit, a demodulator for demodulating the output of the intermediate frequency amplifier circuit and outputting a digital signal, and receiving a constant voltage generated by the demodulator, A constant voltage circuit for supplying a stabilized operating voltage for the high frequency amplifying circuit, the mixing circuit, and the intermediate frequency amplifying circuit, and a tuning frequency change control applied from the frequency synthesizing unit to the antenna tuning unit according to an output of the preconstant voltage circuit. It characterized in that it comprises a switching circuit for controlling the signal Pager with frequency scan function that. 2. The antenna assembly of claim 1, wherein the antenna tuning unit comprises a first capacitor and a second capacitor connected in parallel to the antenna, and a third capacitor connected in series to the first and second capacitors connected in parallel. A capacitor comprising a capacitor of a fixed capacitor and a variable capacitance diode in which a tuning frequency change control signal is applied, and the impedance is changed according to the tuning frequency change control signal applied from the frequency synthesizing unit to determine a tuning frequency. Radio page receiver with scan function. The method of claim 1, wherein the controller compares a memory storing various states of the receiver with a storage signal of the memory and a digital signal of the receiver, and outputs a digital signal of the receiver if the two signals are identical. A decoder that receives information about a pre-signal of another channel, compares a received frequency signal with an error efficiency state, and outputs a comparison result and the pre-signal of the other channel; and calls the user in response to a digital signal of the decoder An output device for outputting a signal, the digital signal of the decoder and the comparison result and a pre-signal of another channel to inform the user of the digital signal through an indicator, and in response to the comparison result and the pre-signal of another channel Select a signal with high error efficiency and select a channel with the signal with high error efficiency. Pager with frequency scanning function comprising the central processing unit sends a channel selection signal to the frequency synthesis unit which can change the program counter. The frequency synthesizer of claim 1, wherein the frequency synthesizer comprises: a reference frequency oscillator for generating a reference frequency, a reference divider for dividing an output of the reference frequency oscillator, and a phase connected to the reference divider for generating a phase difference between the synthesized signal A comparator, a low pass filter for filtering the low pass output of the phase comparator, a voltage controlled oscillator for generating an oscillation frequency applied to the mixing circuit and the antenna tuning unit according to the voltage control signal filtered by the low pass filter, and the center And a program counter for applying the synthesized signal generated by combining the channel selection signal of the processing device and the output of the voltage controlled oscillator to the phase comparator.