Portable paging telephone system with improved response signal verification mode

A portable paging telephone system comprises a mobile telephone terminal device 4 and a base station 6 which form a speech path with a mobile station such as an automobile telephone set or a portable telephone set, as well as a wireless paging terminal device 5 connected to a mobile telephone exchange 3 and a wireless transmission device 7 connected to the wireless paging terminal device are provided. On the other hand, a wireless paging receiver is provided in the portable telephone set. When the portable telephone set is to be called, the wireless paging receiver is paged, through the wireless transmission device, by a paging signal from the wireless paging terminal device. The portable paging telephone system provided a sufficient communication distance in a stand-by mode, reduces a power consumption and permits a compact and long-time-use portable telephone set.

CROSS-REFERENCE TO RELATED APPLICATION 
This application relates to U.S. Ser. No. 07/952,253 (pending) entitled 
"PORTABLE PAGING TELEPHONE SET" being filed by Kazunori Watanabe and 
assigned to the present assignee, based on Japanese Application No. 
3-261773 filed on Oct. 9, 1991 and the content of which is incorporated 
herein by reference. 
BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a portable paging telephone system for 
communicating with a portable telephone set. 
2. Description of the Related Art 
A mobile telephone terminal unit which accommodates a plurality of base 
stations in a prior art portable paging telephone system encodes an 
automobile telephone number or a portable telephone number, that is, a 
mobile telephone number, pages a telephone number by wireless, accepts a 
response signal to the paging during a short time period, commands to 
switch to a channel of the corresponding base station to establish a 
communication channel, confirms the number and connects the calling 
station to the paged telephone. 
However, unlike the automobile telephone, the portable telephone should be 
compact and light weight, to facilitate carrying, and the telephone set is 
folded or an antenna is pushed in a stand-by mode. As a result, during the 
stand-by of the telephone set, an antenna gain is reduced by approximately 
10 dB and a transmission distance is reduced to approximately one half due 
to a city propagation property of an electromagnetic wave. As a result, a 
service area may be reduced to one quarter. 
A power consumed to watch the paging from a base station amounts to one 
third of a maximum speech time assuming that the stand-by time is eight 
hours. 
JPA-2-95035 discloses an additional paging system for an automobile 
telephone set in which a removable paging receiver is attached to a mobile 
station and when a call from a base station is detected, a call signal is 
sent to the paging receiver. It can inform the call to a person who moves 
away from an automobile through the automobile telephone set which has a 
high receiving capacity, but it cannot be applied to the portable 
telephone set. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide a portable paging 
telephone system which provides a sufficient communication distance in a 
stand-by mode, and is for use with a compact portable telephone set in a 
manner to saves reduce power consumption to enable operation for a long 
time. 
In order to achieve the above object, the portable paging telephone system 
of the present invention: 
1) secures a predetermined paging distance from a base station without 
regard to an extended or shortened position of an antenna of a portable 
telephone set by being adapted for use with a wireless paging receiver 
(provided with a built-in antenna) in the portable telephone set, in 
addition to a transmitter receiver of the portable telephone set, and 
2) enables a maximum speech time or reduction in the size of a battery to 
be used in the portable telephone set to in turn reduce the size and 
weight of the portable telephone set by turning off a power of the 
transmitter-receiver during a stand-by mode so that no power is consumed, 
and by turning on the power only during a speech mode. 
In accordance with the present system, since the system powers only the 
wireless paging receiver in the portable telephone set during the stand-by 
mode and powers the transmitter-receiver only during the speech mode, the 
power consumption of the portable telephone set is reduced, and long-time 
use, compactness and wide area communication are attained.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIG. 1, numeral 1 denotes a telephone set of a sender or a 
calling terminal station which is a stationary terminal station, numeral 2 
denotes an end office which accommodates a plurality of stationary 
terminal stations, numeral 3 denotes a mobile telephone exchange connected 
to the end office, numeral 4 denotes a mobile telephone terminal device 
connected to the mobile telephone exchange, numeral 5 denotes a wireless 
paging terminal device connected to the mobile telephone exchange, numeral 
6 denotes a wireless base station of the mobile telephone set for 
wireless-communicating with a portable telephone set, numeral 7 denotes a 
wireless paging transmission station connected to the wireless paging 
terminal device 5, and numeral 4b denotes an interface between the mobile 
telephone set and the wireless paging terminal device. 
FIG. 2 shows a more detailed block diagram of FIG. 1. In FIG. 2, numeral 4a 
denotes a mobile telephone connecting device, numeral 4c denotes a switch 
for switching telephone lines, numeral 5a denotes a paging signal device 
for generating a paging signal to be sent to the wireless paging receiver, 
numeral b denotes a memory for storing a portable telephone number, 
numeral 5c denotes a memory for storing a sending station number which has 
paged the portable telephone set, numeral 5d denotes an announcing device 
for inquiring the sending station number from the wireless paging terminal 
device 5, and numeral 5e denotes a transfer device of signals from memory 
5b and memory 5c to devices 5d and 4b; these signals indicate various 
numbers such as the portable telephone number to be paged, the sending 
station number and a reference number. A temporary memory (not shown) for 
storing those numbers is provided in the interface 4b and they are 
utilized for the collation of an ID number of the portable telephone set 
which responded to the wireless paging, the sending station number and the 
reference number. Numerals 71 and 72 denote wireless transmission stations 
for wireless paging, numerals 7a and 7b denote service areas of those 
transmission stations and numerals 61 to 66 denote base station wireless 
devices for the mobile telephone set such as the automobile telephone set 
and the portable telephone set. The Japanese mobile telephone system uses 
of a paging channel (PCH) for paging the mobile telephone, an access 
channel (ACH) for accepting a call from the mobile telephone set, and a 
plurality of speech channels (SCH). The U.S. cellular mobile telephone 
system uses a control channel (CCH) for accepting the paging and the 
mobile call and identifying a speech channel, and a plurality of speech 
channels (SCH). The service area 7a of the transmission device 71 which 
pages the wireless paging receiver and sends a message covers a plurality 
of areas 6a, 6b and 6c of the mobile telephone base stations 61, 62 and 
63. 
Referring to FIG. 2, an operation of the portable paging telephone system 
of the present invention is explained. It is now assumed that a phone 
number of the portable paging telephone set sent from the calling 
telephone set 1 is 03-6##-***** where "03" is an area code, "6" plus two 
digits following the "03" indicate the call to the portable paging 
telephone set and a system code, and the following five digits indicate 
the ID number of the portable paging telephone set. Hundreds of thousands 
of mobile telephone sets may be registered in one system. 
The phone number of the portable paging telephone set received from the end 
office 2 is applied to a line B of the wireless paging terminal device 5 
through a line B of the mobile telephone exchange 3 and the switch 4c of 
the interface 4b. 
On the other hand, when the calling telephone number received from the end 
office 2 is for a mobile telephone set, the telephone number is applied to 
a line A of the mobile telephone terminal device 4 from a line A of the 
exchange 3. The number is checked, and it is combined with the call number 
of the mobile telephone connecting device 4a and sent through the paging 
channels P-CH of the wireless base stations 61, 62 and 63 for paging. The 
speech channel (SCH) is designated, and the connection is made with the 
calling station to start the speech. 
The call to the wireless paging receiver (with the built-in antenna) of the 
portable telephone set is applied to a line C of the wireless paging 
terminal device 5 from a line C of the mobile telephone exchange 3, it is 
coded by the paging signal device 5a and it is sent out from the wireless 
transmission station as a paging signal. The paging signal is sent out two 
or three times at a given interval. 
The call signal to the portable paging telephone set applied to the line B 
of the wireless paging terminal device 5 is stored in the portable 
telephone number memory 5b. The wireless paging terminal device 5 is 
requested by device 5d to inform the telephone number of the calling 
station so as to store this telephone number in memory 5c, as a message. 
The telephone number of the calling station with the addition of the 
reference number is stored in the calling station number memory 5c. Those 
number data are transferred to the paging signal device 5a and the 
interface 4b of the mobile telephone terminal device 4 from the connecting 
signal transfer device 5e. 
The signal of the paging signal device 5a is sent out in the same manner as 
a conventional paging signal, and it is received by the wireless paging 
receiver (with the built-in antenna) of the portable paging telephone set, 
and the reference number and the calling station number are stored in the 
memory of the wireless paging receiver of the portable telephone set as 
the message. The portable paging telephone set derives from this stored 
message a message signal for transmitting to a wireless base station 
device. The paging call may be made one time or several times as required 
to capture the portable telephone set. On the other hand, the telephone 
line of the calling station is switched to the mobile telephone terminal 
device by the switch 4c through the line D of the wireless paging terminal 
device 5, and the message signal from the portable paging telephone set 81 
is compared with the message signal from the interface 4b. If they match, 
the opposite portable telephone set is connected to the telephone set of 
the calling station through the telephone line of the line B to start the 
speech. 
A calling operation from the portable paging telephone set 81 is now 
explained. When a call is to be made from the portable paging telephone 
set 81, the shortened antenna is extended and the folded telephone set is 
expanded to power on the transmitter-receiver. Before this operation, the 
power has been kept off and only the wireless paging receiver 
intermittently receives the call signal. The wireless paging receiver can 
operate for receiving for one month by a single battery due to the 
power-conservation achieved by this invention. The reception of a call may 
be displayed as required. 
When the wireless paging receiver (with the built-in antenna) of the 
portable telephone set detects a call, it rings a bell to inform the 
reception of the call. Alternatively, a soundless vibration by a vibration 
motor may be used to inform the reception of the call. 
Then, the portable telephone set is activated to capture the access channel 
A-CH of the mobile telephone. When the telephone set is hooked off, the 
data of the message is sent to the base station through the channel A-CH. 
The base station compares the data of the message signal from the portable 
paging telephone set with the data of the interface 4b, and if they match, 
it connects the portable telephone set to the calling station through the 
telephone line B. 
The portable paging telephone system of the present invention offers the 
following advantages, as seen from the above embodiment; 
1) Since the wireless paging receiver is mounted in the portable telephone 
set to monitor the call from the base station, the transmitter-receiver 
need be used only during speech mode, and the power consumption during 
stand-by is reduced and long-time use of the telephone set is assured; and 
2) Since the service area of the wireless paging receiver is broader than 
the service area of the mobile telephone set, wide area communication is 
attained.