JP3232012B2 - Mobile communication method, communication device, and housing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is very weak in transmitting information (hereinafter, referred to as downlink) from a fixed communication device (hereinafter, referred to as a base station) to a movable communication device (hereinafter, referred to as a radio terminal). The present invention relates to a mobile communication system that uses visible light or infrared light to transmit power radio waves from a wireless terminal to a base station (hereinafter, referred to as uplink).

[0002]

2. Description of the Related Art Recently, wireless mobile communication has been rapidly increasing as seen in personal handy phone systems (PHS), portable telephone systems and the like. While these mobile communication systems using radio have the convenience of being able to move and use wireless terminals anywhere, for example,
When a wireless terminal is used in a hospital, there is a serious problem that a malfunction occurs in a medical device or the like. This malfunction is caused by the following reasons.

[0003] Generally, in mobile communication, radio communication is possible between a radio terminal and a radio base station. For this reason, the radio base station and the radio terminal generate radio waves of electric power that can reach the other party. When the wireless terminal is a mobile phone system, the peak power is 600 milliwatts to 2 watts, PH
In the case of S, a radio wave is output with a peak power of about 80 milliwatts. If the wireless terminal is movable, it may be used near the medical equipment or the like. The radio waves output from the wireless terminal reach the medical device or the like with little attenuation because the distance from the wireless terminal to the medical device or the like is short, and generate inductive noise in the internal electronic circuit, thereby causing a malfunction. cause.

On the other hand, radio waves of almost the same intensity are radiated from the base station. For example, even in the case of a PHS base station, it is installed at a place away from medical equipment such as the ceiling of a room, and has a strong radio wave. Since the electric field strength is inversely proportional to the distance, the radio wave from the wireless base station is very weak near the wireless terminal and does not have enough power to affect the medical equipment and the like.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a mobile communication system which eliminates malfunctions of the medical equipment and the like and ensures mobility of a radio terminal. Is to provide.

[0006]

According to the present invention, in order to eliminate malfunctions of the medical equipment, etc., visible light or infrared light is used instead of radio waves in the prior art for uplink from a radio terminal to a radio base station. The most main feature of the downlink from the wireless base station to the wireless terminal is to use radio waves in order to enable incoming calls even when the wireless terminal moves out of the visible light or infrared communication range.

In the present invention, light or infrared light is used for an uplink from a wireless terminal to a wireless base station. Since visible light and infrared light are not radio waves, even if they are radiated near the medical equipment or the like, there is no effect on the electronic circuit. On the other hand, for the downlink from the wireless base station to the wireless terminal, conventional radio waves are used, but the power is very weak near the wireless terminal, and the power that affects the medical device and the like is very low. No. Therefore, it is possible to eliminate the malfunction of the medical device and the like that has occurred in the related art.

[0008] Further, since radio waves of the prior art are used for the downlink, it is possible to receive a call even if the wireless terminal is moved to a range that cannot be reached by light and infrared rays. Communication can be enabled by moving the wireless terminal to a range where light or infrared communication is possible. Also, when the wireless terminal is a portable wireless terminal, there is an advantage that even if the terminal is put in a pocket or a bag, there is no effect on the incoming call .

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION

[Embodiment 1] An embodiment of the present invention will be described with reference to FIGS. 1, 2, 3 and 4 using PHS as an example. FIG. 1 is a configuration diagram of a wireless communication system for explaining the present invention.
Is a wireless terminal, 1-10 is a light emitting unit of the wireless terminal, 1-2 is a wireless base station, 1-20a, 1-20b,.
Is an optical receiving unit of the wireless base station, 1-3 is a communication network, 1-4 is uplink light from the wireless terminal 1-1 to the wireless base station 1-2, and 1-5 is wireless from the wireless base station 1-2. Downlink radio waves to the terminal, 1-6 is a line from the radio base station to the communication network,
1-7 are terminals accommodated in the communication network 1-3. 1. Optical receivers 1-20a, 1-20b of wireless base station 1-2
-20n are distributed and installed in the wireless coverage area of the wireless base station 2.

When a call is received from the terminal 1-7 accommodated in the communication network 1-3 to the wireless terminal 1-1, the communication network 1-3 goes down from the wireless base station 1-2 closest to the wireless terminal 1-1. A call signal is transmitted by a link radio wave 1-5. The wireless terminal 1-1 rings an internal ringer in response to a call signal from the wireless base station 1-2 to notify the user of an incoming call. The user is the optical receiver 1 of the wireless base station 1-2.
-20a, 1-20b,..., 1-20n, move to the range of the optical receiving unit (1-20a in the explanatory diagram of FIG. 1) capable of optical communication, and transmit the light emitting unit 1 of the wireless terminal 1-1. -10 is opposed to the optical receiver 1-20a of the wireless base station 1-2, and responds to an incoming call. That is, usually, the user moves freely with the wireless terminal, and when there is an incoming call, the user only needs to move near the optical receiving unit of the wireless base station. Moreover, since only light is emitted from the terminal, no malfunction occurs even when a medical device or the like is nearby.

FIG. 2 is a diagram showing the configuration of the radio base station.
.., 21n are communication information receiving buffers connected to the optical receivers 1-20a, 1-20b,.
-23 is a radio oscillation circuit, 1-24 is a modulation circuit, 1-25
Is a TDMA / TDD processing unit, 1-26 is a voice codec conversion unit, 1-27 is a control unit, 1-28 is a network interface unit, 1-31a, 1-31b,. is there.

The uplink light 1-4 from the light emitting unit 1-10 of the wireless terminal 1-1 is photoelectrically converted by the optical receiving unit 1-20a, and is temporarily stored in the receiving buffer 1-21a.
It is taken in accordance with the processing timing of the MA / TDD processing unit 1-25, converted from 32 kbit / sec to 64 kbit / sec by the voice codec conversion unit 1-26, and transmitted via the network interface unit 1-28. Sent to Information from the communication network 1-3 is conversely transmitted to the network interface unit 1-2.
8, voice codec converter 1-26, TDMA / TDD
The signal is sent to the modulation circuit 1-24 via the processing unit 1-25,
The signal is modulated and oscillates in the radio oscillation circuit 1-23, and is radiated as radio waves into the air through the radio wave radiation antenna 1-22.
The TDMA / TDD processing unit 1-25 performs transmission / reception control based on the communication time schedule shown in FIG.

FIG. 3 is a block diagram of the wireless terminal 1-1.
1-11 is a control unit, 1-12 is a transmission buffer, 1-13
Is a reception antenna, 1-14 is a radio wave reception unit, 1-15 is a demodulation unit, 1-16 is a TDMA / TDD processing unit, 1-17 is a voice codec, 1-18 is a microphone, 1-19 is a speaker, 101 is an operation unit, 1-102 is a display unit, 1-1
03 is a ringer.

The audio is input from a microphone 1-18, digitized and compressed by an audio codec 1-17, and then subjected to TDM.
The signal is processed according to the timing of the A / TDD processing unit 1-16, sent to the transmission buffer 1-12, subjected to electro-optical conversion by the light emitting unit 1-10, and then emitted into the air as uplink light. The received radio wave is taken into a radio wave receiving unit 1-14 via a receiving antenna 1-13, demodulated by a demodulation unit 1-15, processed according to the timing of a TDMA / TDD processing unit 1-16, and processed by a voice codec 1-14. The signal is converted into an analog signal at 17 and output as sound from the speaker 1-19.

FIG. 4 shows a communication time schedule for one frame of TDMA / TDD between the radio base station and the radio terminal in the PHS. In the current PHS standard, one wireless base station can simultaneously communicate with three wireless terminals.

In FIG. 4, radio terminal A, radio terminal B,
It is assumed that the wireless terminal C is communicating. # 1T, # 2
T, # 3T, and # 4T are transmission timings from the wireless base station 1-2 to each of the wireless terminals A, B, and C. # 1T is a transmission timing of a control signal common to each of the wireless terminals A, B, and C. 2
T, # 3T, and # 4T are transmission timings of communication information for each of the wireless terminals A, B, and C. # 1R, # 2
R, # 3R, and # 4R are reception timings from the wireless terminals in the wireless base station 1-2, and # 1R is each wireless terminal A,
Reception timing of control signals from B and C, # 2R, # 3
R and # 4R indicate the timing of receiving communication information from each of the wireless terminals A, B and C. The timing on the wireless terminal side corresponding to the timing in the wireless base station 1-2 is such that reception is # 1Ra, # 1Rb, # 1Rc, # 2Ra,
# 3Rb, # 4Rc, and transmission is # 1Ta, # 1T
b, # 1Tc, # 2Ta, # 3Tb, # 4Tc.

A control signal (transmission timing # 1T) from the radio base station is received by all radio terminals near the radio base station 1-2. At the time of calling from the wireless terminal and receiving from the communication network, the wireless base station 1-2 uses the control timings (# 1T and # 1R) to set the communication timing for communicating with the wireless terminal to # 2, # 3. , # 4. Control signals and communication information from the wireless base station are received and buffered by each wireless terminal, and then processed.
Control signals and communication information from the wireless terminals are transmitted to the optical receiving units 1-20a, 1-20b,... 1-2 of the wireless base station 1-2.
0n, control signal receiving buffers 1-31a provided for
1-31b,... 1-31n and communication information receiving buffers 1-21a, 1-21b,. That is, communication can be realized without changing the communication time schedule of the PHS as shown in FIG. Therefore, the communication protocol used in the PHS can be used as it is.

The embodiment in which the present invention is implemented in the PHS has been described above. By making the uplink part of the PHS light, malfunctions of medical equipment and the like can be eliminated, and the PHS can be realized by replacing only the part related to the uplink of the wireless base station and the wireless terminal with an optical communication compatible circuit. The system can be made very economical. In this embodiment, the optical receiving unit of the wireless base station communicates with the wireless terminal on a one-to-one basis.

In this embodiment, a wireless terminal that uses radio waves for both transmission and reception is used, and a light emitting unit having a housing separate from the wireless terminal is connected to the wireless terminal to operate the wireless terminal. The object of the present invention can be achieved by preventing the wireless oscillation circuit of the terminal from operating.

Embodiment 2 FIG. 5 is a view showing a second embodiment of the present invention, wherein 2-1 is a shielded housing for accommodating a portable radio terminal, 2-11 is a receiving antenna of the shielded housing, Reference numeral 2-12 denotes an optical transmission unit of a shielded housing, 2-2 denotes a PHS terminal, 2-3 denotes an optical receiver, 2-4 denotes a PHS base station, and 2-51 denotes a cable connecting the optical receiver and the base station. -52 is a cable connecting the base station and the private branch exchange.

FIG. 5 employs a PHS as a representative system, but it can be applied to a communication system in which another communication area uses a small zone of several hundred meters.

The feature of this embodiment is that it is not necessary to notify a telephone number or the like to a partner because a PHS terminal already provided with a service can be used as it is.

When a terminal such as a PHS is used near a medical device, the electromagnetic wave causes the medical device to malfunction.
Therefore, in the present embodiment, the portable wireless terminal is the shield housing 2-1.
It is to be stored and used. Usually, the electric field intensity generated by the portable wireless terminal is about 20 V / m near the antenna, so if the shielding performance is 20 dB or more, the electric field intensity leaking to the outside of the housing is about 2 V / m, and the immunity target value of the medical device IEC 601-1-2, which is 3 V / m, which is the standard. The shielding effect of 20 dB can be easily realized by putting a metal net of about 1/10 of the wavelength in plastic.

The housing 2-1 has a receiving antenna, and re-radiates radio waves received from the base station into the housing. Therefore,
The portable wireless terminal can receive a radio wave even in the case. On the other hand, the radio wave transmitted from the portable wireless terminal is converted into an optical signal by the casing 2-1 and emitted. The radiated optical signal is received by the optical receiver and sent to the receiving section of the base station.
The base station performs mobile communication by treating the same as when receiving a radio wave. Again,
Since an optical signal is used for the uplink, as described in the first embodiment, there is a problem that it takes time to answer a call, but it can be solved by changing the program of the private branch exchange.

FIG. 6 shows a shielding housing 2 for housing a portable radio terminal.
-2 indicates an electronic circuit portion of the shielding housing;
2-14 is a transparent plastic part, 2-15 is a hole for passing sound, and 2-21 is an antenna of a portable wireless terminal.

It is necessary to enable the operation of the stored portable wireless terminal from the outside in the shielded housing 2-2. Therefore, a transparent and soft plastic is used for a portion of the portable wireless terminal having a key and a display. In addition, a hole is made in the place where the ear and the mouth hit to pass sound. In the case of PHS, the wavelength is about 15 cm. Therefore, when a metal net (a net of a conductor embedded in plastic) is used, the interval is 1.
The thickness may be set to 5 cm or less, and sufficient transparency and softness can be obtained.

FIG. 7 shows the configuration of the electronic circuit section 2-13 of the shielded housing. Reference numeral 2-13a denotes a receiving antenna for receiving a transmission radio wave radiated from the portable radio terminal, and 2-13b denotes the reception signal. An amplifier, 2-13c is a driving circuit of a light emitting element such as a semiconductor laser, 2-13d is a transmitting antenna for transmitting a signal received by the receiving antenna 2-11 of the shielding housing to an antenna of a portable wireless terminal, and 2-13e is Amplifier, 2-
13f is a bandpass filter.

The communication signal received by the receiving antenna 2-11 is filtered by a bandpass filter 2-13f to remove unnecessary frequency components, and then amplified by an amplifier 2-13e to be amplified.
Antenna 2-21 of portable wireless terminal radiated from 13d
Received at. On the other hand, the radio wave transmitted from the portable wireless terminal is received by the antenna 2-13a, and is received by the amplifier 2-13a.
After being amplified by b, it is sent to the light emitting element drive circuit 2-13c, and emitted to the space by the light emitting element 2-12 as an optical signal. This electronic circuit employs a system in which a radio wave transmitted from a portable radio terminal is directly analog-modulated and transmitted, and has an advantage that an existing radio system or circuit can be used. In the present electronic circuit, amplifiers and filters that are already used in portable wireless terminals such as PHS can be used. On the other hand, for a light emitting element and a driving circuit, for example, if a semiconductor laser is used, analog modulation up to about several GHz is possible.

FIG. 8 shows a circuit configuration of the optical receiver 2-3, where 2-3a is a photodetector and 2-3b is an amplifier. As the light detecting element, for example, a PIN photodiode is used. The output of the photodetector is amplified and transmitted to the base station 2-
4 is sent to the receiving unit.

FIG. 9 shows another configuration of the electronic circuit section 2-13 of the shielding housing, and 2-13g is a frequency conversion circuit.

In this circuit, the transmission signal of the portable radio terminal received by the antenna 2-13a is once converted to a low frequency and radiated as an optical signal via the light emitting element. By using this method, there is an advantage that an inexpensive light emitting element such as an LED can be used.

FIG. 10 shows a circuit configuration of the optical receiver 2-3 corresponding to the circuit configuration shown in FIG. 9, and 2-3c is a frequency conversion circuit. After the output of the photodetector is amplified,
Converted to the frequency used by the base station,
4 is sent to the receiving unit. In this case, by arranging the frequency conversion circuit near the base station, it is possible to use an inexpensive coaxial cable that may have a large loss in a high frequency region of about 1 GHz or more for the cable 2-51, and at the same time to use the optical receiver and There is an advantage that the base station can be kept away.

Embodiment 3 FIG. 11 is a view showing a third embodiment of the present invention, wherein 2-6 is a building, 2-7 is an external antenna installed outside the building, and 2-2 is a portable telephone. is there. In the case of mobile communication employing a large zone such as a mobile phone, since the base station is far away, as shown in the figure, the optical signal detected by the optical receiver 2-3 installed in each room is converted into an electric signal. After the signal is converted into a signal, the transmission radio wave of the mobile phone is re-emitted from the outdoor antenna. Since the outdoor antenna is installed outside the building sufficiently distant from medical equipment and the like, it has no influence.

As a shielding housing for accommodating a mobile phone,
The optical receivers shown in FIGS. 6, 7, and 9 can be used as the optical receivers shown in FIGS.

[0035]

As described above, by using the PHS system to make the uplink in the wireless section light, malfunctions to medical equipment due to radio waves are eliminated, and the downlink remains radio waves. By doing so, it is possible to know the incoming call at the destination, and since most of the circuits and communication protocols of the wireless base station and the wireless terminal and the communication protocol can be used as they are, there is an advantage that they can be realized at low cost.

[Brief description of the drawings]

FIG. 1 is a system configuration of an embodiment of the present invention.

FIG. 2 is a configuration of a wireless base station according to the embodiment of the present invention.

FIG. 3 is a configuration of a wireless terminal according to an embodiment of the present invention.

FIG. 4 is a communication time schedule of a wireless section according to the present invention.

FIG. 5 is a diagram showing a second embodiment of the present invention.

FIG. 6 is a shielded housing for housing a portable wireless terminal.

FIG. 7 shows a configuration of an electronic circuit unit 2-13 of the shielding housing.

FIG. 8 is a circuit configuration of an optical receiver 2-3.

FIG. 9 is another configuration of the electronic circuit unit 2-13 of the shielding housing.

10 is an optical receiver 2 corresponding to the circuit configuration shown in FIG.
3 is a circuit configuration.

FIG. 11 is a third embodiment of the present invention.

[Explanation of symbols]

1-1 wireless terminal 1-10 light emitting section of wireless terminal 1-2 wireless base station 1-20a, 1-20b,... 1-20n optical receiving section of wireless base station 1-3 communication network 1-4 wireless terminal Uplink light from 1-1 to wireless base station 1-2 1-5 Downlink radio wave from wireless base station 1-2 to wireless terminal 1-6 Line from wireless base station to communication network 1-7 Communication network 1 Terminals accommodated in -3 1-2a, 1-21b,... 1-21n Communication information receiving buffers connected to optical receiving units 1-20a, 1-20b,. 1-23 Radio oscillation circuit 1-24 Modulation circuit 1-25 TDMA / TDD processing unit 1-26 Voice codec conversion unit 1-27 Control unit 1-28 Network interface unit 1-31a, 1-31b, ... 1-31n Control signal reception buffer 1 11 control unit 1-12 transmission buffer 1-13 reception antenna 1-14 radio wave reception unit 1-15 demodulation unit 1-16 TDMA / TDD processing unit 1-17 audio codec 1-18 microphone 1-19 speaker 1-101 operation unit 1-102 Display Unit 1-103 Ringer 2-1 Shielding Case for Accommodating Portable Wireless Terminal 2-11 Receiving Antenna of Shielding Case 2-12 Light Transmitting Unit of Shielding Case 2-2 PHS Terminal 2-3 Light Reception 2-4 PHS base station 2-51 Cable connecting optical receiver and base station 2-52 Cable connecting base station and private branch exchange 2-13 Electronic circuit section of shielded housing 2-14 Transparent plastic section 2-15 Sound 2-21a Antenna of portable wireless terminal 2-13a Receiving antenna for receiving transmission radio wave radiated from portable wireless terminal 2-13b Increasing received signal 2-13c Driving circuit of light emitting element such as semiconductor laser 2-13d Transmitting antenna for transmitting a signal received by receiving antenna 2-11 of shielded case to antenna of portable wireless terminal 2-13e Amplifier 2-13f Band filter 2-3a Photodetector 2-3b Amplifier 2-3c Frequency conversion circuit 2-6 Building 2-7 External antenna installed outside building 2-8 Mobile phone

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04B ⁷ /24-7/26 H04B 10/00-10/28 H04Q 7/00-7/38 H04L 12/00-12 / 62

Claims (8)

(57) [Claims] 1. A communication method between a fixed communication device connected to a communication network and at least one mobile communication device, which is susceptible to radio waves transmitted from the mobile communication device. A mobile communication method for using said mobile communication device in an ambient environment, said mobile communication device comprising:
Transmits information using radio waves, and the fixed communication device
From the movable communication device located at an arbitrary position in the radio wave cover area to the fixed communication device ,
Connected to a fixed communication device and separated into the radio wave coverage area
Of the plurality of light receiving units that are scattered and installed,
Which can communicate with a mobile communication device
Information transmission using visible light or infrared light
The mobile communication method reduces the influence of the radio wave transmitted from the mobile communication device on the surrounding environment. 2. The fixed communication device sends a call signal to the mobile communication device using the radio wave, and the mobile communication device that receives the call signal uses the visible light or infrared light. When it is located in a range where it can communicate with any of the light receiving sections connected to the fixed communication device using the visible light or infrared light.
The mobile communication method according to claim 1, wherein an incoming response signal is transmitted to the fixed communication device via an optical unit . 3. A fixed communication device connected to a communication network, at least one movable communication device, and a fixed communication device and a transmission communicable with the movable communication device.
A receiving device, and covering the mobile communication device;
20dB or more of radio waves leaking from mobile communication devices to the outside
The communication method with a housing that has a shielding function to attenuate
Kicking, wherein a mobile communication method for using the portable telecommunications apparatus in a movable radio-sensitive environment transmitted from the communication device, receiving device provided in the housing Is the fixed
The radio wave transmitted from the communication device is installed outside the housing.
Received by the receiving antenna, and set the radio wave inside the housing.
From the placed transmitting antenna to the mobile communication device
The transmission / reception device provided in the housing is provided with the movable communication device.
The radio wave transmitted from the communication device is installed inside the casing.
Received by the receiving antenna, and the radio waves are
To the fixed communication device from the transmitting and receiving device provided in the housing , is connected to the fixed communication device, the
Coverage of radio waves transmitted from fixed communication devices
Arbitrary position among multiple light receiving units
Communication with the housing covering the movable communication device located at
Visible light or infrared light via any possible light receiving part
A mobile communication method characterized by reducing the influence of radio waves transmitted from the movable communication device on the surrounding environment by transmitting information using a line . 4. The transmission / reception device provided in the housing converts the radio wave received from the movable communication device directly into an optical signal at the same frequency as the radio wave. Mobile communication method as described. 5. A transmission / reception device provided in the housing uses a light intensity modulation method for modulating the radio wave received from the movable communication device by the intensity of a reception signal of the radio wave. The mobile communication method according to claim 4. 6. A fixed communication device connected to a communication network and at least one movable communication device capable of communicating with the fixed communication device and a surrounding area susceptible to radio waves transmitted from the movable communication device. A housing for using the mobile communication device in an environment, wherein a radio wave leaking outside from the mobile communication device is 20 d
A shielding means for attenuating B or more, and a radio wave transmitted from the fixed communication device,
Means for receiving with a receiving antenna installed outside the body,
The radio wave is transmitted from the transmitting antenna installed inside the housing.
Means for transmitting to a mobile communication device.
Receiving means for transmitting radio waves transmitted from the movable communication device to the housing;
Means to receive with a receiving antenna installed inside the body, and
Means for converting the radio wave into visible light or infrared light;
Transmitted visible light or infrared light to the fixed communication device
Housing, characterized in that it comprises a second transceiver means for chromatic and means, the for. 7. The apparatus according to claim 1, wherein the means for converting the radio wave into visible light or infrared light converts the radio wave received from the movable communication device directly into an optical signal at the same frequency as the radio wave. 7. The housing according to 6 . 8. The means for converting the radio wave into visible light or infrared light uses a light intensity modulation method for modulating the radio wave received from the movable communication device by the intensity of a reception signal of the radio wave. The housing according to claim 7 .