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Mobile Phone Patent Abstract
A mobile phone set includes a base unit and at least one handset
belonging to the base unit. In the base unit, a receiving section
11 receives a first modulated wave S.sub.1 which is a digital modulated
wave from TX 3, and a demodulating section 12 demodulates the received
wave, and further a decoding section 13 decodes the demodulated
wave. Further, a detecting section 17 detects the demodulated wave.
Further, a detecting section 17 detects that the decoded signal
is of a calling signal for the handsets 2-1 and 2-2 associated with
the base unit, and after the detection a controlling section 25
instructs a D/A converting section 14 to D/a convert a digital signal
decoded by the decoding section 13 to an analog signal and a modulating
section 15 to modulate the analog signal. A transmitting section
16 transmits a second modulated wave S.sub.2 as the analog modulated
wave to the handset 2-1 or 2-2. Further, in the base unit 1, a receiving
section 18 receives a third modulated wave S.sub.3 as the analog
modulated wave from the handset 2-1 for example, and a demodulating
section 19 demodulates the received wave.
Mobile Phone Patent Claims
What is claimed is:
1. A mobile phone set comprising:
a base unit and at least one handset, said base unit being for
digital radio communication with a fixed transmitting station and
for analog radio communication with said handset, said base unit
comprising:
a first receiving section for receiving a first modulated digital
wave transmitted from the fixed transmitting station and for converting
the first modulated wave to a first modulated digital signal;
a first demodulating section for demodulating said first modulated
signal to create a first demodulated signal;
a first detecting section for detecting whether or not the first
demodulated signal is of a signal to the base unit;
a first modulating section for modulating said demodulated signal
to generate a second modulated analog signal for transmission to
the handset;
a first radio transmitting section for converting the second modulated
analog signal to a second modulated analog wave and for transmitting
the second modulated analog wave to said handset;
a second receiving section for receiving a third modulated analog
wave transmitted from said handset and for converting the third
modulated analog wave to a third modulated analog signal;
a second demodulating section for demodulating said third modulated
signal to create a second demodulated signal;
a second detecting section for detecting whether or not the second
demodulated signal is of a signal of itself;
a controlling section for instructing radio transmission to said
handset after receiving a detection signal from said first detecting
section and for instructing radio transmission to said fixed transmitting
station after receiving a detecting signal from said second detecting
section;
a second modulating section for modulating the second demodulated
signal from said second demodulating section to create a fourth
modulated digital signal for transmission to said fixed transmitting
station; and
a second radio transmitting section for converting the fourth modulated
digital signal to a fourth modulated digital wave and for transmitting
the fourth modulated digital wave to said fixed transmitting station.
2. A mobile phone set according to claim 1 wherein each said handset
comprises:
a receiving section for receiving the second modulated analog wave
which is an analog modulated wave from the base unit;
a demodulating section for demodulating the second modulated wave;
an electric signal-speech converting section for converting the
demodulated signal to a speech;
a detecting section for detecting that the demodulated wave is
of a signal of itself;
a speech-electric signal converting section for converting a speech
signal to an electric signal;
a modulating section for modulating the electric signal from the
speech-electric signal converting section;
a transmitting section for transmitting the third modulated wave
from the modulating section as an analog modulated wave;
a calling section for issuing an informing signal when said detecting
section detects that the demodulated signal is of a signal of itself;
and
a controlling section for controlling each operation of each circuit
component.
Mobile Phone Patent Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a mobile communication system
and a mobile radiotelephone set.
2. Description of the Prior Art
Although mobile radiotelephones (hereinafter referred to as "mobile
phone") are popularized at present, such prior art mobile phone
are usable only inside a mobile. Use thereof outside the mobile
requires some measures, say in one measure, a phone set body installed
ordinarily inside the mobile is taken out of the mobile together
with a transmitter/receiver or a handset and they are carried on
a shoulder of a user.
Noticed that there has been prevailed recently a cordless telephone
for radio communication between a base unit and a handset, construction
of a mobile phone with such base unit a handset permits the base
unit to be installed intactly inside the mobile, which further allows
communication from the outside of the mobile simply by carrying
out and using the handset outside the mobile.
This enables a mobile phone comprised of a base unit and a handset
to be realized with a digital communication system, but it is thereupon
desired to achieve the circuit construction of an entire system
in a simplified manner and at a low cost to the utmost.
SUMMARY OF THE INVENTION
To solve the difficulties with the prior art, it is an object of
the present invention to provide a low cost mobile phone system
and set with a simplified circuitry capable of utilization even
outside a mobile.
To achieve the above object, a mobile phone set comprises a base
unit and at least one handset capable of radio transmission/reception
with said base unit, said base unit being capable of digital transmission/reception
between a fixed transmitting station and the base unit and the handset
being capable of analogue transmission/reception between the base
unit and the handset.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view exemplarily illustrating a mobile radio communication
system including a mobile phone set according to the present invention;
and
FIG. 2 is a block diagram illustrating a preferred embodiment of
a mobile phone set according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In what follows, there will be described the present invention
with reference to the accompanying drawings.
An embodiment of a mobile phone set according to the present invention
comprises a base unit installed inside a mobile and at least one
handset.
Referring to FIG. 1, there is illustrated a mobile radio communication
system including a mobile phone set.
The mobile radio communication system comprises a fixed transmitting
station (hereinafter referred to as a TX) 3, a base unit 1 mounted
on a mobile 4 located in a radio zone Z.sub.T for a fixed transmitting
station which is a communication region mediating a digital modulated
wave of an electric wave transmitted from TX 3, and handsets 2-1
and 2-2 each located in a radio zone Z.sub.M for a mobile phone
set which is a communication region mediating an analog modulated
wave of an electric wave transmitted from the base unit in the mobile.
Both handsets 2-1 and 2-2 have the same structure and the same circuitry
and operate in the same manner.
Once the base unit 1 of the present invention receives a signal
to the handsets 2-1 and 2-2 associated with the base unit 1 from
TX 3 in the radio zone Z.sub.T, the base unit 1 converts the signal
to an analog modulated wave and transmits it to the handsets 2-1
and 2-2 located in the radio zone Z.sub.M. Further, an analog modulated
wave transmitted from the handset 2-1 for example is received by
the base unit 1 which then converts the analog modulated wave to
a digital modulated wave and transmits it to TX 3.
Referring to FIG. 2, there is illustrated an embodiment of a mobile
phone set according to the present invention in a form of a block
diagram.
As illustrated in FIG. 2, a mobile phone set of the present embodiment
comprises a base unit 1 and a handset 2-1 or 2-2 belonging to the
base unit 1.
The base unit 1 comprises a receiving section 11 for receiving
section 11 for receiving through an antenna Al a first modulated
wave S.sub.1 (digital modulated wave) transmitted from a fixed transmitting
station TX a demodulating section 12 for demodulating the first
modulated wave, a decoding section 13 for decoding a first demodulated
wave demodulated by the demodulating section 12, a detecting section
17 for detecting whether or not a decoded signal is of a signal
directed to the base unit 1, a D/A converting section 14 for converting
the decoded signal to an analog signal to transmit the same signal
to the handset 2-1, a modulating section 15 for modulating a converted
analog signal to a second modulated wave (analog modulated wave),
a transmitting section 16 for transmitting through an antenna A.sub.2
the second modulated wave to the handset 2-1, a receiving section
18 for receiving a third modulated wave (analog modulated wave)
transmitted from the handset 2-1, a demodulating section 19 for
demodulating the third demodulated wave, a detecting section 24
for detecting whether or not the third modulated wave is of a signal
to the base unit 1, an A/D converting section 20 for converting
an output from the demodulating section 19 to a digital signal,
an encoding section 21 for encoding the digital signal from the
A/D converting section 20 for transmission to a digital signal fixed
transmitting station TX, a modulating section 22 for modulating
an encoded digital signal to a second modulated wave (digital modulated
wave), a transmitting section 23 for transmitting the second modulated
wave to the fixed transmitting station, and a control section 25
for controlling the whole of the base unit 1.
Likewise, as illustrated in FIG. 2, the handset 2-1 comprises a
receiving section 26 for receiving through an antenna A.sub.3 the
second modulated wave S.sub.2 (analog modulated wave) transmitted
from the base unit 1, a demodulating section 27 for demodulating
the second modulated wave, an electric signal-speech converting
section 28 for converting the demodulated signal to a speech, a
detecting section 29 for detecting that the demodulated wave is
a signal of itself, a speech-electric signal converting section
31 for converting a speech signal to an electric signal, a modulating
section 32 for modulating the electric signal from the speech-electric
signal converting section 31, a transmitting section 33 for transmitting
a third modulated wave S.sub.3 from the modulating section 32 therefrom
as an analog modulated wave, a calling section 34 for generating
a calling signal after receiving a call, a called part for issuing
an informing signal when the foregoing detecting section 29 detects
that the demodulated signal is of a signal of itself, and a controlling
section 35 for controlling the operation of the respective circuit
components.
Operation of the present embodiment will be described with reference
to FIGS. 1 and 2.
In the base unit 1, the receiving section 11 receives the first
modulated wave S.sub.1 which is a digital modulated wave from TX
3, and the demodulating section 12 demodulates the received signal,
and further the decoding section 13 decodes the demodulated wave.
Further, the detecting section 17 detects that the decoded signal
is of a calling signal for the handset 2-1 owned thereby, and the
controlling section 25 instructs, after the detection, the D/A converting
section 14 to D/A convert the digital signal decoded by the decoding
section 13 into the analog signal. The modulating section 15 thereafter
modulates the analog signal, and the transmitting section 16 transmits
the second modulated wave S.sub.2 as the analog modulated wave to
the handset 2-1.
Further, in the base unit 1, the receiving section 18 receives
the third modulated wave S.sub.3 which is an analog modulated wave
transmitted from the handset 2-1 for example, and the demodulating
section 19 demodulates the received wave, and further the detecting
section 24 detects that the demodulated signal is of a signal of
itself. The controlling section 25 instructs, after the detection,
the A/D converting section 20 to A/D convert the demodulated analog
signal wave to a digital signal, and the encoding section 21 encodes
the digital signal. The modulating section 22 modulates the encoded
signal and the transmitting section 23 transmits the third modulated
wave as the digital modulated wave to TX 3.
In contrast, in the handset 2-1, the receiving section 26 receives
the second modulated wave S.sub.2 which is an analog modulated wave
from the base unit 1, and the demodulating section 27 demodulates
the received wave and further the detecting section 29 detects that
the demodulated wave is of a signal of itself. The controlling section
35 instructs, after the detection, the informing section 30 to issue
an informing signal. Thereafter, once the informing section 30 receives
a called signal, the controlling section 35 issues the electric
signal-speech converting section 28 to convert the demodulated signal
wave to a speech, while once it receives a speech signal, the controlling
section 35 issues the speech-electric signal converting section
31 to convert the speech signal to an electric signal, and the modulating
section 32 modulates the electric signal and the transmitting section
33 transmits the third modulated wave S.sub.3 as an analog modulated
wave.
Further, in the handset 2-1, the calling section issues a calling
signal after receiving a call, and the modulating section 32 modulates
the calling signal and the transmitting section 33 transmits the
modulated wave. Thereafter, the receiving section 26 receives the
second modulated wave S.sub.2 and the modulating section 27 modulates
the received wave, and the detecting section 29 detects that the
modulated wave is of a called signal. The controlling section 35
instructs, after the detection, the electric signal-speech converting
section 28 to convert the demodulated signal wave to a speech, while
the speech-electric signal converting section 31 converts a speech
signal after receiving the same to an electric signal. The modulating
section 32 modulates the electric signal and the transmitting section
33 transmits the third modulated wave S.sub.3 as an analog modulated
wave.
It is self-evident now that provided the D/A converting section
14 is altered to the A/D converting section 20 in the present embodiment,
a base unit may be realized where an analog modulated wave received
from TX is converted to a digital modulated wave and transmitted
to the handset 2-1, and that provided the D/A converting section
14 and the A/D converting section 20 are eliminated, or provided
they are altered to the encoding section 21, respectively, a base
unit 1 is realized where a digital modulated wave received from
the TX is transmitted to the handsets 2-1 and 2-2 as a digital modulated
wave.
In the embodiment shown in FIG. 2, the base unit 1 has two antennas
A.sub.1 and A.sub.2 for separate purposes, however a single antenna
may be use for these purposes.
According to the present invention, as described above, the following
effects ensured:
1) The mobile phone set is useable outside a mobile.
2) Power is supplied from a battery at all times, so that the child
radiotelephone set is reducible in its size compared with prior
art portable radiotelephone sets.
3) The base unit executes many functions required after the radio
waves from TX are received, and the handset may singly have only
low functions, so that the entire apparatus is made light-weighted.
4) A digital communication system is realized in a mobile phone
set with handsets of a simple circuitry.
5) Some radio communications are possible with a single mobile
phone set. |