KR0138886B1 - Method & apparatus interfacing transmission adapor of paging signal - Google Patents

Abstract

The present invention relates to a connection apparatus capable of transmitting or receiving a radio call signal and an improved method of transmitting / receiving a radio call signal using the apparatus, wherein the radio call signal transmission method of the present invention provides an analog signal from a radio call exchanger. Demodulate a digital signal, multiplex the demodulated signal, and transmit it to a base station on a single line using a digital data transmission apparatus (DSU), demultiplexing the transmitted signal again at a base station and modulating an analog signal. The apparatus of the present invention is characterized in that it is configured to modulate and demodulate a radio call signal in order to implement the transmission method. According to the present invention, it is possible to drastically reduce the number of dedicated lines required between an exchange and a base station. It features.

Description

Radio call signal transmission and transmission connection device and transmission method using the device

1 is a conventional radio call signal transmission configuration diagram;

2 is a diagram illustrating a configuration of radio call signal transmission using the present invention;

3 is a schematic diagram of a wireless call signal transmission using the present invention;

4 is a schematic diagram of a demodulation and code digital signal transmitter;

5 is a schematic diagram of a modulation and telephone-level analog signal transmitter;

6 illustrates the definition of a multiplex code format;

FIG. 7 is a diagram showing all the embodiments of a key up signal in case of an analog key up SPOCSAG radio call signal; FIG.

8 shows a part of an embodiment of radio call data;

FIG. 9 is a detailed view of FIG. 2 showing a coupling relationship between a radio call exchanger and a demodulation device of the present invention; FIG.

FIG. 10 is a detailed view of FIG. 3 showing a coupling relationship between a radio call exchanger and a demodulation device of the present invention; FIG.

FIG. 11 is a supplementary diagram of FIGS. 2 and 3 showing a coupling relationship between the modulation apparatus of the present invention and the radio call transmitter.

* Explanation of symbols for main parts of the drawings

1, 31: overvoltage and overcurrent protection circuit

2, 30: transformer for impedance matching

3: Key-Up Signal Detection Circuit

4: Self test signal detection and no power signal detection circuit

5, 14: Transmission status selector 6, 13: Transmission status display part and drive part

7, 15: control unit and data storage unit 8: radio call signal demodulation circuit

9: Wireless call signal synchronization recovery and synchronization signal generation circuit

10: transmission data synchronization unit 11, 12: EIA RS-232 connection unit

16: Self test signal detection circuit 17: Wireless call signal modulation circuit

18: modulation signal transmission power control circuit

19: wireless call signal start detection and modulation signal transmission control circuit

20: key-up signal transmission control circuit

21, 22: key-up signal generating circuit 23, 24: low pass band filter

25, 26: key-up signal transmission power control circuit

27: key-up signal mixing circuit 28: outgoing signal mixing circuit

29: Low pass band filter and termination power amplifier circuit

32: output data synchronizing signal generating circuit and resynchronizing circuit

33: Format of analog radio call signal

34: Format of Multiplexed Code (Digital Radio Call Signal)

35: digital key-up multiplexing code 36: analog key-up multiplexing code

37: Synchronization signal of multiplex code 38: Type of keyup

39: Type of code 40: Start of keyup

41: Start of Function Tone (FT)

42: Start of Silence Gap 43: Start of Radio Call Data

44: wireless call data

45: embodiment of 'analog keyup' in 'analog radio call signal'

46: Embodiment of 'control signal' in 'digital radio call signal (multiplex code)'

47: Example of 'wireless call data' in 'analog wireless call signal'

48: Embodiment of 'wireless call data' in 'digital wireless call signal (multiplex code)'

The present invention relates to an apparatus capable of transmitting or receiving a radio call signal and an improved method of transmitting / receiving a radio call signal. Particularly, an analog radio call signal is converted into a digital signal. And a method for restoring a received digital signal to an analog radio call signal, and a method for transmitting a radio call signal by using the apparatus to drastically reduce the number of dedicated lines required between an exchange station (central station) and a base station (terminal station). will be.

The wireless call signal transmission method of the mobile communication currently in operation, as shown in FIG. 1, which shows a wireless call signal transmission system according to the existing method, uses one line per channel between the switching center and the base station, respectively. It uses a wired transmission line (telephone analog dedicated line) for transmission. However, according to the conventional radio calling signal transmission method, as the service area becomes wider and the number of subscribers increases, the number of base stations and the number of channels increases, thereby greatly increasing the number of dedicated lines required between the switching center and the base station. do. That is, as illustrated in FIG. 1, if the number of base stations is m and the number of service channels is n, m x n transmission lines are required. As a result, according to the conventional method, the budget is wasted due to enormous leased line cost expenditure due to the increase of the leased line, and there are many difficulties in securing and maintaining the leased line. In addition, there is a problem in that the line quality is degraded due to the use of a telephone-grade analog line and the reliability thereof is lowered. Accordingly, the present invention is made to solve this problem,

In the transmission method according to the present invention, an analog radio call signal transmitted from a wireless call exchanger of a mobile communication through a connection device according to the present invention, in particular, a POCSAG and SPOCSAG signal is converted into a digital signal, and the digital signal is multiplexed (Multiplexer). Multiplexing the signal, and transmitting the multiplexed signal to the base station through a code level digital line or satellite, and demultiplexing the code level signal transmitted from the demultiplexer of the base station to apply the signal to the access device according to the present invention. Through the connection device according to the present invention, the digital signal is restored to an analog radio call signal and transmitted to the transmitter.

The apparatus for transmitting and receiving radio call signals according to the present invention is characterized in that it is possible to modulate and demodulate radio call signals, in particular, POCSAG and SPOCSAG signals. Until now, since the apparatus for modulating and demodulating the radio call signal has not been developed, the radio call signal cannot be multiplexed. Therefore, the access device according to the present invention has been invented to realize the radio call signal transmission method according to the present invention.

In realizing the radio call signal transmission method according to the present invention, the general multiplex transmission method should not be used, and an improved multiplex transmission method should be used for the present invention. This is due to the simulcasting of the signal, which is implemented to solve the problem that occurs when the pager receives the same call at different times when the pager receives the radio call signal in the key region of several terminal stations. Modulation and demodulation device of the present invention is designed to implement the concurrency of the signal by using the multiplexed transmission scheme outlined.

Hereinafter, the configuration of the present invention will be described with reference to the accompanying drawings.

In the demodulation device for transmitting a wireless call signal according to the present invention, as shown in FIG. 'And' the 'impedance matching transformer (2)' and the 'impedance matching transformer' are connected in parallel to the signal through the 'impedance matching transformer (2)' is simultaneously applied in the form of an unbalanced signal, 'wireless Send the demodulation signal of the call-up signal demodulation circuit 8, the key-up signal detection circuit 3 and the no-power signal detection circuit 4, and the key-up signal to the EIA RS-232 connection 11; 'Data storage unit and control unit for transmitting the power-free signal to the connection unit through the' transmission data synchronization unit 10 'and storing data using the synchronization signal generated by the' wireless call signal synchronization recovery circuit 9 '. 7) 'and the' control unit 7 'can set the transmission status and environment It is composed of a "transmission state selection unit 5," and "display unit 6, which displays the transmission state or an abnormal state.

As shown in FIG. 5, the modulator for transmitting the wireless call signal according to the present invention is connected to the 'EIA RS-232 connection unit 12' and the 'key-up signal transmission control circuit 20' is inputted when the key-up signal is input. A 'key storage signal and control unit 15' for controlling and storing data transmitted from a transmitting side, and a 'key up signal generating circuit 21 controlled by the' key up signal transmission control circuit 20 'connected to the control unit. And a 'low pass band filter 24' which is directly connected to the 'key-up signal generating circuit' and narrows the band of the key-up signal, and a 'power output control circuit 25' which adjusts the intensity of the signal as necessary. A keyup signal mixing circuit 27 to which the keyup signal is applied, a wireless call signal modulation circuit 17 for modulating data into an analog signal from a data storage unit, and controlling transmission of the modulated signal 'Power transmission control circuit 18' and the 'wireless call signal modulation circuit' 'Wireless call signal start detection circuit 19' for controlling only the actual data portion of the modulated signal to be transmitted, and 'output data sync signal generation circuit 32' connected to the 'control unit' to generate a synchronization signal. And an 'outgoing signal mixing circuit 28' for making the modulated signal and the key-up signal into a single signal form, and the 'low pass pass filter 29' for connecting the single signal to each other in series. An impedance matching transformer 30, an overvoltage and overcurrent protection circuit 31, and a transmission state selector 14 and a display 13 connected to the controller.

The first radio call signal transmission method according to the present invention comprises the steps of demodulating an analog radio call signal from a radio call exchanger into a digital signal (multiplexing code), multiplexing the demodulated signal, and multiplexing the multiplexed signal. Transmitting to a base station by a single line using a digital data transmission apparatus (DUS), demultiplexing the transmitted signal at a base station, modulating the demultiplexed code into an analog radio call signal, and transmitting the same to a transmitter It consists of steps.

In the second method of transmitting a radio call signal according to the present invention, demodulating an analog radio call signal from a radio call exchanger into a digital signal (multiplexing code), multiplexing the demodulated signal, and transmitting the multiplexed signal to a satellite transmitter. Transmitting to the satellite using the VSAT, receiving a signal transmitted through the satellite at a satellite receiver Hub, demultiplexing the transmitted signal, and analogizing the demultiplexed code. It modulates the radio call signal and transmits it to the transmitter.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

In the present invention, the data format 34 of the 'digital radio call signal' (hereinafter, referred to as 'multiplex code') in which the 'analog radio call signal 33' of FIG. 6 is converted to be transmitted through a multiplexer and The transmitter control signal (Key-Up) and the silence power signal (Silence Gap) of the same analog radio call signal correspond to a control signal of several bytes, and the radio call data uses the same format.

35 and 36 in FIG. 6 are examples of multiplex codes. Actually displayed values are ASCII code values of 1 byte. These values can be defined as desired in Firm Ware. (37) indicates the beginning of the multiplexing code. The value is fixed at 96h. (38) represents the 'type of keyup'. There are two types of keyups: digital keyups and analog keyups. The digital key-up is a modulated digital signal, and the analog key-up is a tone type composed of HLGT (Function Tone) and FT (Function Tone). 'D' means Digital Key-up and 'A' means Analog Key-up. Reference numeral 39 denotes a 'signaling method'. Signaling methods are POCSAG and SPOCSAG. 'P' for POCSAG and 'S' for SPOCSAG. 40 denotes 'start of the keyup signal'. In case of analog keyup, it marks the start of HLGT. It is fixed to '$'. (41) indicates 'start of FT' as required value only for analog keyup. Fixed to '#'. Reference numeral 43 denotes 'the end of the keyup signal'. That is, "start of radio call data 44" is displayed. Fixed value of '%'.

7 and 8 are actual waveforms for the case of the analog key-up SPOCSAG signal in the defined state as shown in FIG. 45 is the actual waveform of the analog keyup in the analog radio call signal. (46) is the TTL waveform of the 'multiplex code control signal' for (45). Reference numeral 47 is an actual waveform of a part of the radio call data in the 'analog radio call signal'. (48) is the TTL waveform of 'multiplex code radio call data' for (47). The analog radio call signal is composed of 45 and 47, and the digital radio call signal (multiplexing code) thereof is composed of 46 and 48.

A transmission system using a connection device of the present invention will be described with reference to FIGS. 2 and 3, and FIG. 11 shows a coupling relationship between the connection device (modulator) and the radio call transmitter of FIG.

2 is an embodiment of a method for transmitting a radio call signal using a DDS network. In the radio call exchanger, m channels of analog radio call signals are transmitted for each of m channels and applied to m x n interconnection apparatuses (demodulation apparatuses) of the present invention through a 6000 balanced two-wire telephone line. 9 is a detailed diagram of the coupling relationship between the radio call exchanger and the connection device (demodulation device) of FIG. 2. Each analog radio call signal is a digital radio call signal (multiplexing code) in the connection device (demodulation device) of the present invention. Is converted to. The digital radio call signals (multiplex codes) are applied to m multiplexers of n units in accordance with ELA RS-232 connection standards. The digital radio calling signal (multiplexing code) of n channels is multiplexed through each of the m multiplexers. The m multiplexed signals are applied to m digital data transmitters (DSUs) according to the ELA RS-422 connection standard. The signals are each transmitted by a digital data transmission apparatus (DSU) on a single line through a DDS network and received by m base station DSUs. At each base station, the signal is applied to the demultiplexer according to the ELA RS-422 connection standard. The signal is demultiplexed into a digital radio calling signal (multiplexing code) of n channels by the demultiplexer. The digital radio call signal (multiplexing code) of the n channels is applied to the n connection devices (modulators) of the present invention in accordance with the ELA RS-232 connection standard. The n channel digital radio call signal (multiplexing code) is restored to an n channel analog radio call signal in the access device (modulator) of the present invention. The n channel analog radio call signal is transmitted to the transmitter through a 600 kHz two-wire telephone line. 11 is a detailed view of the coupling relationship between the connection device (modulator) and the radio call transmitter of FIG.

3 is an embodiment of a method of transmitting a radio call signal using satellites. The n channel analog radio call signal transmitted from the radio call exchanger is applied to the n connection devices (demodulation apparatuses) of the present invention through a 600 Ω balanced two-wire telephone line. FIG. 10 is a detailed diagram of the coupling relationship between the radio call exchanger and the connection device (demodulation device) of FIG. Each analog radio call signal is converted into a digital radio call signal (multiplexing code) in the connection device (demodulation device) of the present invention. The digital radio call signal (multiplex code) of n channels is applied to one multiplexer according to the EIA RS-432 connection standard. The digital radio calling signal (multiplexing code) of n channels is multiplexed through a multiplexer. The multiplexed signal is applied to a satellite transmitter (VSAT) according to the EIA RS-232 connection standard. The signal is transmitted to the satellite via a satellite transmitter (VSAT) and the signal is received at a satellite receiver (Hub) of each of the m base stations. At each base station, the signal is applied to the demultiplexer according to the EIA RS-422 connection standard. The signal is demultiplexed into a digital radio calling signal (multiplexing code) of n channels by the demultiplexer. The digital radio call signal (multiplexing code) of the n channels is applied to the n access devices (modulators) of the present invention according to the EIA RS-232 connection standard. The digital radio call signal (multiplexing code) of the n channels is provided. Is restored to the n channel analog radio call signal in the access device (modulator) of the present invention. The n channel analog radio call signal is transmitted to the transmitter through a 600 kHz two-wire telephone line. 11 is a detailed view of the coupling relationship between the connection device (modulator) and the radio call transmitter of FIG.

An embodiment of a modulation / demodulation device and a connection device according to the present invention will be described below with examples 45, 47 and 46, 48 of the data format described above.

4 relates to a demodulation device according to the invention. This part converts the analog radio call signal of FIG. 6 transmitted from the exchange into a multiplex code and transmits the multiplex code.

The analog radio call signals 45 and 47 are applied to the primary side of the impedance matching transformer 2 through an overvoltage and surge protection circuit 1 through a line stage. . Since the transmission line is 600 ohm balanced, the primary side of the impedance matching transformer 2 is also designed to be 600 ohm balanced. The signal passing through the impedance matching transformer 2 is applied to the key-up signal detecting circuit 3 and the no-power signal detecting circuit 4 simultaneously as an unbalanced analog wireless calling signal. The two circuits detect the key-up signal and the silence signal 45 in the first half of the analog radio call signal, and the 'control unit 7' analyzes this to form the control signal portion 46 of the multiplexed code. To the EIA RS-232 interface unit 11.

Subsequently, radio call data (preamble and batch signals) 47 of the analog radio call signals are applied to the radio call signal demodulation circuit 8 to demodulate the analog signals into digital signals 48. The demodulated signal 48 is stored in the data buffer 7 by the controller. As the synchronization signal used for storage, the synchronization signal extracted by the 'wireless call signal synchronization recovery circuit 9' from the demodulation signal is used. The control unit transmits the stored digital radio call data 48 to the EIA RS-232 interface unit 11 to complete the multiplexing codes 46 and 48 of the radio call signal.

On the other hand, the synchronization signal used to transmit the multiplex code to the 'EIA RS-232 interface unit' is a clock signal input from the multiplexer and extracted from the 'transmission data synchronization unit 10'. In this way, when inputting (saving) the data to the data storage unit 7 and outputting different synchronization signals (storage: synchronization signal recovered from analog radio call signal, output: external synchronization signal) In this case, data can be transmitted normally even when the transmission rate of the wireless call signal of the exchange is changed.

The 'EIA RS-232 interface unit 11' transmits a multiplex code and a control signal to the outside in the form of an RS-232 signal (CCITTV. 24) defined by the EIA. The control signals DTR and RTS are used to control the multiplexer to implement the simulcasting of the signals.

5 relates to a modulation device according to the invention. The multiplexing code of FIG. 6 transmitted through the demultiplexer through the transmission network is restored to an analog radio call signal transmitted from the exchange and transmitted to the transmitter.

Receives multiplex coded wireless calling signal through 'EIA RS-232 connector'. Control signals (DSR, CTS, DCD) of EIA RS-232 deliver information on the simulcasting of signals transmitted through multiplexers.

The controller 15 recognizes the control signal 46 of the multiplexing code of FIG. 6 and controls the key-up signal transmission control circuit 20 when the analog key-up signal 'A' is detected. The key-up signal transmission control circuit 20 controls the key-up signal generating circuits 21 and 22 according to the key-up signal transmitted as a part for adjusting and controlling the generation of the analog key-up signal according to the key-up signal. HLGT (High Level GUARD Tone) and FT (Function Tone) signals 45 are generated. The key up signal HLGT generation circuit 21 generates a signal of 2175 Hz among the key up signals, and the key up signal FT generation circuit 22 generates a signal of 1950 Hz. The key-up signal is narrowed in the band through the low pass band filters 23 and 24 and further amplified to the required signal strength through the power transmission control circuits 25 and 26. The key-up signal that has passed through the 'output power control circuits 25 and 26' is applied to the 'output signal mixing circuit 28' via the 'key-up signal mixing circuit 27'. In the case of digital key-up, the wireless call data sending circuits of (17) to (19) are used instead of the analog key-up sending circuits of (20) to (27).

The control unit 15 stops the keyup signal transmission and operates the wireless call signal transmission start detection circuit 19 when the non-power signal Silence '' is recognized in the control signal 46 of the multiplex code.

When the 'control unit' recognizes the 'starting wireless call data' ('%'), the wireless call data 48 of the multiplexing code is stored in the 'data storage unit 15'. The stored data is then sent to the 'wireless call signal modulation circuit 17'. The radio call signal modulation circuit 17 modulates the data 48 coming from the data storage unit 15 into analog radio call data 47 of FIG. The modulated signal transmission power control circuit 18 adjusts the transmission power according to the adjustment of the wireless call signal start detection and the modulation signal transmission control circuit 19 and transmits the output signal mixing circuit 28 at the correct time. ) '

When receiving the multiplexing code through the EIA RS-232 interface from the demultiplexer, the clock provided by the demultiplexer uses the synchronization signal. When the wireless call data is output from the data storage unit 15 to the wireless call signal modulation circuit 19, the clock provided by the output data synchronization signal generation circuit and the resynchronization circuit 32 is used as the synchronization signal. use. In addition, the output data synchronizing signal generation circuit and the resynchronization circuit 32 have a resynchronization function and transmit information on the simulcasting information (DSR, CTS, DCD) transmitted through the EIA RS-232 connection unit. Accordingly, the apparatus of the present invention of the various terminal stations can transmit the same signal to the radio call transmitter at the same time when the radio call signal is transmitted.

As a result, all of the analog radio call signals 45 and 47 of FIG. 6 were inputted into the "transmission signal mixing circuit 28". Afterwards, the analog radio call signal passes through the outgoing signal low pass bandpass filter and the termination power amplifier circuit 29, and goes through the impedance matching transformer 30 and the overvoltage and overcurrent protection circuit 31 to the line. It is sent out.

As the common part of FIG. 4 and FIG. 5, the control part 7 (15) controls the various circuits collectively, and has the self test function (4) (16) at the time of checking and initializing the operation state of each part circuit. Therefore, it is possible to determine whether there is an abnormality in each circuit. In addition, it includes a 'transmission status display section 6 (13)' related to the transmission status, and has a function of displaying an alarm status (Alarm) or a transmission status in normal operation when a failure occurs. The transmission status selector 5 or 14 selects various transmission states and environments that are required, namely, a transmission signal method selection [POCSAG (512 bps), SPOCSAG (1200 bps)], and a key up signal method selection (analog key up, digital). Keyup).

According to the present invention, when the transmission path is constructed as shown in FIG. 2, unlike the conventional method of FIG. 1 (m × n telephone-class analog lines), only m code base lines are required ( Considering redundancy, the size is 2 × m), the line cost is reduced, the maintenance is easy, and the digital transmission of the signal improves the transmission quality.

As shown in FIG. 3, when a transmission path is constructed using satellites, a 1: N configuration is used, and one satellite communication channel can be used (two channels in consideration of redundancy) to transmit to each base station. Cost reduction and ease of maintenance and repair are maximized. In addition, due to the nature of the configuration, as shown in FIG. Furthermore, as in the transmission schemes of FIG. 1 and FIG. 2, transmission delay differences caused by different transmission paths can be completely eliminated because they use the same transmission path, and thus high quality and high reliability services can be expected. .

As described above, the present invention provides a demodulation technique for converting an analog radio call signal, in particular, a POCSAG signal and a SPOCSAG signal, into a digital signal type (multiplexing code) that can be multiplexed in a multiplexer, and converts the digital signal (multiplexing code) back to the original. By using the modulation technology to restore the signal (analog radio call signal), the circuit has a significant effect on reducing the conventional circuit between the switching center and the base station, and in the future, the method of multiplexing the analog radio call signal and transmitting the signal is demodulated. Or to belong to the technical scope of the present invention irrespective of the modulation technique. This is based on the fact that the present invention implements the simulcasting of signals that cannot be realized in a general communication network made by a combination of a multiplexer and a transmission device.

Claims (8)

An overvoltage and overcurrent protection circuit (1) and an impedance matching transformer (2) installed in series where a wireless call signal is applied through a line end at an exchange; The wireless call signal demodulation circuit 8, the key-up signal detection circuit 3, and the power-free signal, which are connected in parallel with the impedance matching transformer and are simultaneously applied in the form of an unbalanced signal through the impedance bonding transformer 2 Detection circuit 4; The data storage unit sends a demodulation signal of the key-up signal to the connection unit and transmits a no-power signal to the connection unit through the transmission data synchronization unit according to the method of transmitting the key-up signal, and stores the data using the synchronization signal generated by the radio call signal synchronization recovery circuit. And a control unit 7; A demodulation device for transmitting a wireless call signal, comprising: a transmission state selection unit 5 connected to the control unit 7 to set a transmission state and an environment; and a display unit 6 displaying the transmission state or an abnormal state. . The demodulation device for transmitting a radio call signal according to claim 1, wherein the radio call signal is a POCSAG or SPOCSAG signal. A data storage unit and control unit 15 connected to the connection unit 12 to control the transmission control circuit when the key up signal is input, and to store data for storing data transmitted from the transmission side; A key up signal generation circuit 21 controlled by the key up signal transmission control circuit 20 connected to the control unit; A low pass band filter 24 connected in series with the key up signal generating circuit and narrowing a band of the key up signal; A transmission power adjusting circuit 25 for adjusting the strength of the signal as necessary; A key up signal mixing circuit 27 to which the key up signal is applied; A radio call signal modulation circuit 17 for modulating data from the data storage into an analog signal; A transmission power regulation circuit 18 for regulating the transmission of the modulated signal; A radio call signal start detection circuit (19) connected in parallel with the radio call signal modulation circuit and controlling to transmit only the actual data portion of the modulated signal; An output data synchronization signal generation circuit connected to the control unit to generate a synchronization signal; An outgoing signal mixing circuit 28 for making the modulated signal and the keyup signal into a single signal form; A low pass band filter 29 connected to each other in series to apply the single signal; A modulation circuit for transmitting a wireless call signal, characterized in that it comprises an impedance matching transformer (30), an overvoltage and overcurrent protection (31), and a transmission state selector (14) and a display unit (13) connected to a control unit. The modulator circuit for transmitting a radio call signal according to claim 3, wherein the radio call signal is a POCSAG or SPOCSAG signal. Demodulating an analog signal from a pager into a digital signal; Multiplexing the demodulated signal and transmitting the signal to a base station on a single line using a digital data transmission device (DSU); and demultiplexing the transmitted signal at the base station and modulating the signal into an analog signal. Signal transmission method. 6. The method of claim 5, wherein the radio call signal is a POCSAG or SPOCSAG signal. Demodulating an analog signal from a pager into a digital signal; Multiplexing the demodulated signal and transmitting the satellite signal to a satellite using a satellite transmitter (VSAT); and receiving the transmitted signal from the satellite at a satellite receiver (HUB), demultiplexing the transmitted signal and modulating it into an analog signal. Wireless call signal transmission method characterized in that. 8. The method of claim 7, wherein the radio call signal is a POCSAG or SPOCSAG signal.