JPS63226131A - Broad band radio communication system - Google Patents

Abstract

PURPOSE:To attain call communication even when a mobile equipment is moved to an optional district without assigning a broad hand frequency by receiving a modulation wave signal having a frequency corresponding to a preamble word received and detected. CONSTITUTION:A modulation wave signal corresponding to a cell signal is sent from a transmission station only in the district to a pager receiver for the district and a call signal is transferred through a line between central stations Cj to a broad band pager receiver and the modulation wave signal having the allocated frequency is sent from all transmission stations Tji. Moreover, a pager receiver Pk uses the selection means 1 of the received frequency to select a receptible frequency and a detection means 2 detects a preamble word to control the selection means so as to receive the frequency represented by the preamble word. Thus, even if a pager receiver Pk is moved to a different district, the allocated frequency of the district is received. Thus, the broad band communication is attained without assigning any frequency for the broad band purpose.

Description

[Detailed Description of the Invention] [Summary] In a paging system in which a different frequency is assigned to each region and paging communication is performed for a pager receiver, each transmission is added with a preamble word that can identify the frequency corresponding to the region. The pager receiver includes preamble word detection means and reception frequency selection means,
By receiving a modulated wave signal of a frequency corresponding to the detected preamble word, calling communication is possible even when moving to any area without allocating a wide area frequency.

[Industrial application field]

The present invention relates to a wide area wireless communication system that performs paging communication using a pager receiver equipped with reception frequency selection means.

In a paging system that transmits modulated wave signals of the same frequency from a plurality of transmitting stations connected to a central station and performs paging communication for pager receivers within the area consisting of the service area of each transmitting station, Different frequencies are assigned to each region, and therefore, when a pager receiver for use within a region is moved to another region, paging communications cannot be made.

Therefore, by using a regional frequency and a wide-area frequency common to each region, a pager receiver that can receive the regional frequency can perform paging communications within each region and receive the wide-area frequency. There is a system that uses a wide area pager receiver to enable paging communication even when moving to a different area. In that case, it is necessary to use two types of frequencies, one for local use and one for wide area use, and two types of pager receivers, one for local use and one for wide area use. It is requested.

[Conventional technology]

In the conventional wide area wireless communication system, for example, as shown in FIG.
, C2 are connected to a plurality of transmitting stations T11 to T23, respectively, and each transmitting station is connected so that the service area of the transmitting stations Tll to T13 covers the region L1, and the service area of the transmitting stations 721 to T23 covers the region L2. The location and number of stations have been selected.

Further, frequency F1 is assigned to region L1, frequency F2 is assigned to region L2, and frequency Fc is assigned for wide area use. The central stations CL and C2 are connected by a line 100 to transfer wide area calling signals. Again 1
01 and 201 are connected to the central stations CI and C2, respectively,
This is an exchange that accommodates subscribers 102 and 202. Also, if the pager receiver PI is for the local area and the pager receiver P2 is for the wide area, the pager receiver 41P1 is for the area T-1 and has a configuration that can receive the frequency F1, and the pager receiver P2 is configured to receive the frequency Fc. It has a configuration that allows it.

For example, when a subscriber 102 performs communication for the pager receiver P1 via the switching center 101, since the pager receiver P1 is registered in the switching center 101 as a regional one, the pager receiver P1 is transmitted via the central office C1. 4) The local calling signal is transferred to each transmitting station Tl1-T13, and the modulated wave signal of frequency F1 is transmitted.

Thereby, a paging communication for the pager receiver P1 is performed.

Furthermore, when the subscriber 102 calls the pager receiver P2 via the switching center 101, the pager receiver P2 is registered in the switching center 101 as a wide-area user, The calling signal for each transmitting station Tl
1 to T13, and also to the central station C2 in another area L2 via the line 100, and the paging signals are transferred to the transmitting stations T21 to T23, respectively. Then, a modulated wave signal having a wide area frequency Fc is transmitted from each of the transmitting stations Tll to T23. Therefore, the pager receiver P
2, calling communication is possible even when moving from area L1 to area L2.

Furthermore, a method is known in which the pager receivers PI and P2 are provided with a character display device, etc., and not only a call is made by sounding a buzzer, but also simple character information is transmitted and displayed.

Further, the formant of the modulated wave signal transmitted from each transmitting station Tll to T23 is, for example, as shown in FIG.
Similarly, eight pieces of data Dnl to Dn8 are made into a batch Bn, and a preamble word PW consisting of a synchronization signal is added to the beginning of the batch Bn. Also, the last hatch is 8
If the number of data does not become eight, dummy data is added so that there are eight data. The communication speed of these is, for example, 51'2 b/s.

FIG. 6 shows a block diagram of the main parts of a conventional transmitting station, with 30
0 is a transmitting station, 301 is a regional transmitter, 302 is a wide area transmitter, 303, 304 are antennas, 305, 306
is a signal line. A local calling signal is transferred from the central station via the signal line 305, and a modulated wave signal in the formant shown in FIG. 5 is transmitted from the transmitter 301 at the local frequency F1 or F2. Further, a wide area calling signal is transferred from the central station via a signal line 306, and a modulated wave signal having the form shown in FIG. 5 is transmitted from the transmitter 302 using a wide area frequency FC. The antennas 303 and 304 are
Although they can be provided separately for regional and wide area use, it is also possible to share them via a combiner.

[Problem that the invention seeks to solve]

In the conventional paging system, a wide area frequency Fc is allocated in addition to local frequencies Fl and F2, which poses a problem in terms of effective frequency utilization. It is also necessary to manufacture two types of pager receivers PI and P2: one for local use and one for wide area use. Furthermore, since the transmitting station 300 needs to be provided with transmitters 301 and 302 for local and wide areas, the installation space for these becomes large and costs increase.

Also, between the central station and each transmitting station, there are two types, one for regional and one for wide area.
It is necessary to install two signal lines 305 and 306, which has the disadvantage of making the system expensive.

The present invention eliminates the need to allocate frequencies for wide areas.
The purpose is to enable wide area wireless communication.

[Means for solving problems]

The wide area wireless communication system of the present invention uses a pager receiver that has a function of selectively receiving frequencies,
This will be explained with reference to FIG.

Each transmitting station Tji (j, i=1, 2, 3...)
are respectively distributed and connected to the central station Cj, and the central stations Cj are also connected by lines, and different frequencies Fj are assigned to each area Lj. Each transmitting station Tji transmits a modulated wave signal to which a preamble word indicating the assigned frequency of each region Lj is added. Also, pager reception 4i1JPk (k=1, 2, 3.-
-) comprises reception frequency selection means l and preamble word detection means 2, detects and identifies the preamble word by the detection means 2, and controls the selection means 1 so that the identified allocated frequency can be received. .

[Effect]

For regional pager receivers, modulated wave signals corresponding to the paging signal are transmitted only from transmitting stations within that region.
To the wide-area pager receiver, the ejection signal is transferred through the line between the central stations Cj, and modulated wave signals based on the assigned frequencies are transmitted from all the transmitting stations T j i .

Further, the pager receiver Pk selects a receivable frequency by the reception frequency selection means 1, detects a preamble word by the detection means 2, and controls the selection means 1 to receive the frequency indicated by the preamble word. do. Therefore, even if the pager receiver Pk moves to a different area, it can receive the assigned frequency for that area, so wide area communication is possible without having to allocate a frequency for wide area use.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a detailed explanatory diagram of the present invention.
The configuration of each transmitting station Tji is selected so that each region Lj is covered by the service area of multiple transmitting stations Tji, and each region Lj is connected to the central station Cj by a public line, etc. has been done. The central stations Cj are also connected via public lines, etc.

The pager receiver Pk also includes reception frequency selection means l;
and a preamble word detection means 2. Note that a pager receiver for a region can be configured to be able to receive only the assigned frequencies of the region. In addition,
L i, has 1, 2.3. ...is...

As shown in Fig. 2, a modulated wave signal is transmitted from the transmitting station Tji in a format consisting of a preamble word PW followed by batches B1, B2゜..., and the preamble word PW is synchronized. For example, in region L1, the assigned frequency F
As an identification signal indicating 1, [×...X0OIJ (
X is optional) is inserted. Similarly, the identification signal in area L2 is "×...×010", the identification signal in area L3 is "×...×011", and the identification signal in area L4 is [×... xlooJ is inserted.

Also, each hatch Bl, B2. ...is, as mentioned above,
It consists of data compatible with eight pager receivers.

The pager receiver pk has, for example, the configuration shown in FIG. 3, where 1 is a receiving frequency selection means, 11 is a mixer, 12 is a demodulator, 13 is a synthesizer, 14 is a counter, and 15 is a control unit. 2 is a preamble word detection means, 21 is a decoder, and 22 is a detection identification section. The receiving signal selection means 1 includes a mixer 11. Demodulator 12. Synthesizer 13, counter 14. A case is shown in which the receiving frequency is selected by being configured by the control unit 15 and switching the frequency of the output signal of the synthesizer 13. The detection means 2 is constituted by a decoder 21 and a detection/identification section 22, which decodes the demodulated signal and identifies the identification signal in the detection/identification section 22.

The received high frequency signal is transferred from the high frequency section (not shown) to the mixer 1.
Added to 1. This mixer 11 includes a synthesizer 1
The output signal of mixer 1 is added as a local oscillator signal.
The output intermediate frequency signal of 1 is applied to a demodulator 12 and demodulated. When the carrier detection signal at that time is applied to the control section 15, the control section 15 stops the counting operation of the counter 14. The synthesizer 13 switches the output signal frequency according to the contents of a counter 14 that counts clock signals, and the counter 14 controls the operation m'.
ft, the receiving frequency is being scanned according to the period of the clock signal.

Then, when the operation of the counter 14 is stopped, the output signal frequency of the synthesizer 14 is fixed to the frequency at that time.

Pager receivers registered for regional use, e.g.
A paging communication to the pager receiver P1 in the area L2 is sent to the transmitting station T2 connected to the central station C2 of the area L2.
Frequency F2 assigned to the area only from 1 to T23
A modulated wave signal is transmitted. Therefore, even if the pager receiver P1 has the receiving frequency selection means 1, when moving to another area, the paging communication service cannot be received because the paging signal is not transferred to the other area. This means that you will not be able to do so.

In addition, for paging communications to pager receivers registered for wide area use, since the paging signal is transferred to each central station Cj, modulated wave signals are transmitted from all transmitting stations T j i at the frequency Fj assigned to that area. Sent. For example, in region L1, modulated wave signals having the signal format shown in FIG. 2 are transmitted from each of the transmitting stations T11 to T13 at frequency F1. If a pager receiver Pk exists in the area L1,
When a modulated wave signal of frequency F1 is received while the synthesizer 13 is scanning the reception frequency and a carrier detection signal is obtained from the demodulator 12, the control unit 15 stops the operation of the counter 14, so that the frequency F1 is It becomes possible to receive data continuously.

Then, the preamble word ° demodulated by the demodulator 12
The PW identification signal is decoded by the decoder 21,
It is added to the detection and identification section 22. In this case, since the identification signal is [×...xoolJ indicating the frequency F1, the identification result is transferred to the control unit 15. Control unit 15
identifies the content of the counter 14 in the stopped state, and if the content is such that the frequency F1 can be received, the output signal frequency of the synthesizer 13 is determined to be correct, and the reception state of the frequency F1 is maintained. Also, if the identification signal has contents other than those mentioned above, the frequency of the received signal whose carrier was first detected is
Since the frequency F1 is different from the frequency F1 assigned to this area L1, the control unit 15 restarts the operation of the counter 14 to scan the receiving frequency. Therefore, since the receiving frequency is not determined only by carrier detection, error-free paging communication is possible.

Also, whether or not the call is to the own pager receiver is determined by each hatch B1, B2 .
It can be identified by the pager receiver assignment code, etc. indicated by the data in .... Also, registration as to whether a pager receiver is for a local or wide area is done at the central station CJ or the switching station before it, and in response to a paging communication request for a wide area pager receiver, the paging signal is sent to all central stations. It is transferred to the transmitting station Tji via Cj.

[Effects of the Invention] As explained above, the present invention transmits a modulated wave signal to which a preamble word PW indicating the assigned frequency Fj of each region Lj is added from the transmitting station Tji, and the detection means 2 of the pager receiver Pk It detects and identifies the preamble word PW and controls the selection means 1 so that it can receive a modulated wave signal of the frequency indicated by the preamble word PW, and wide area wireless communication is possible without allocating a wide area frequency. Therefore, effective use of frequencies can be achieved.

In addition, since each transmitting station Tji only needs to be equipped with a transmitter for one frequency, it is possible to connect the central station 01 and transfer a wide area paging signal, in contrast to a paging system that performs paging communication only within an area. Wide-area wireless communication becomes possible by simply adding a configuration that enables economicalization. In addition, the pager reception mPk detects the area Lj by carrier detection and detection identification of the preamble word PW.
Since the assigned frequency Fj is identified, there is an advantage that malfunctions can be prevented.

[Brief explanation of the drawing]

Fig. 1 is a detailed explanatory diagram of the present invention, Fig. 2 is an explanatory diagram of the signal format of the embodiment of the invention, Fig. 3 is a block diagram of the main part of the receiver of the embodiment of the invention, and Fig. 4 is a conventional diagram. An illustration of an example,
FIG. 5 is an explanatory diagram of a conventional signal formant, and FIG. 6 is a block diagram of a main part of a conventional transmitting station. 1 is a reception frequency selection means, 2 is a preamble word detection means, Lj is a region, Fj is a frequency, Cj is a central station,
Tji is a transmitting station.

Claims (1)

[Claims] In a wireless communication system in which a different frequency (Fj) is assigned to each region (Lj) in which a plurality of transmitting stations (Tji) are distributed, and a pager receiver (Pk) performs paging communication. The modulated wave signal with a preamble word indicating the assigned frequency (Fj) of each region (Lj) is sent to the transmitting station (Tji).
The pager receiver (Pk) includes reception frequency selection means (1) and preamble word detection means (2), and the detection means (2) selects the assigned frequency (Fj
), the selection means (1) is controlled, and a modulated wave signal from the transmitting station (Tji) is received.