[go: up one dir, main page]

WO2002058282A1 - Radio communication system comprising an internal and an external antenna part connected via a digital signal transmitting cable - Google Patents

Radio communication system comprising an internal and an external antenna part connected via a digital signal transmitting cable Download PDF

Info

Publication number
WO2002058282A1
WO2002058282A1 PCT/SE2002/000090 SE0200090W WO02058282A1 WO 2002058282 A1 WO2002058282 A1 WO 2002058282A1 SE 0200090 W SE0200090 W SE 0200090W WO 02058282 A1 WO02058282 A1 WO 02058282A1
Authority
WO
WIPO (PCT)
Prior art keywords
external
internal
station
communication system
switch connector
Prior art date
Application number
PCT/SE2002/000090
Other languages
French (fr)
Inventor
Hans-Peter Kurz
Original Assignee
Blue2Space Ab
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Blue2Space Ab filed Critical Blue2Space Ab
Publication of WO2002058282A1 publication Critical patent/WO2002058282A1/en

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving

Definitions

  • Radio communication system comprising an internal and an external antenna part connected via a digital signal transmitting cable
  • the present invention relates to a communication system according to the preamble of the independent claim.
  • the invention relates to radio communication devices and antenna systems thereof.
  • the coverage of every radio communication is limited by the receiver sensitivity, the output power, the antenna gain radiation characteristics of the transmitting antenna, the antenna gain characteristics of the receiving antenna, the location of the transmitting antenna and the location of the receiving antenna.
  • the fundamentals of radio propagation are described in the Friische Formulas.
  • This invention is about taking all the above mentioned parameters into account, especially the antenna gain radiation characteristics of the transmitting antenna, the antenna gain characteristics of the receiving antenna, the location of the transmitting antenna and the location of the receiving antenna.
  • Short link radio devices are getting more and more popular. Mobile phones are becoming a more central point of the everyday life and many ongoing developments show that more and more electronic components/ devices will be connected with each other and especially with the Internet.
  • Bluetooth, IEEE 802.11, hyperlan and homeRF are three examples of a variety of industrial efforts. This invention tries to expand the existing coverage of an RF system.
  • US-5,828,341 discloses a laptop computer having an internal radio with interchangeable antenna features.
  • a switch is provided, arranged to selectively connect the communication device with one of the dedicated antenna and the external antenna.
  • the external antenna is connected to the communication device via an RF cable, e.g. a coaxial cable.
  • US-5,930,728 addresses the problem in a 1900 MHz communication system when an antenna is placed in an attic or other raised elevation a large coaxial cable must be used to carry a 1900 MHz signal as a result of cable attenuation resulting from these frequencies.
  • large is meant a cable with approximately a % inch diameter.
  • a lower frequency e.g. 900 MHz, having lower attenuation in the cable, solves the above-mentioned attenuation problem.
  • a smaller diameter coaxial cable may then be used.
  • Another disadvantage is that the state of the art is limited to one RF part with a certain receiver sensitivity and output power. Even if some users would agree to pay the costs for a more sophisticated RF performance, the price/ dB ratio is always adjusted to the bulk of users and their demands and cost demands.
  • FIG. 1 shows a system according to the state of the art.
  • a communication device 2 is communicating or receiving information from another communication device (not shown).
  • the device has an antenna 10, fixed to the device 2, an RF part 6 and a switch connector part 8.
  • a connector 12 is adapted to be connected to the connector switch 8.
  • the RF transmission line 14 e.g. a coaxial cable, connects the external antenna 16 with the RF part 6.
  • the internal antenna 10 is then switched off.
  • a typical example of the state of the art is a TV with an internal TV antenna. Usually the coverage is not sufficient inside homes. Therefore an external directional antenna, mounted on the roof of the house is connected via a coaxial cable to the TV.
  • a coaxial cable is connecting an external antenna, mounted outside the car, with the mobile phone. Once the external antenna is connected into the mobile phone the mobile phone antenna gets switched off. The coverage increases resulting in less dropped calls.
  • the object of the present invention is to overcome the above-mentioned drawback in prior art systems related to the attenuation in coaxial cables, especially in high frequency systems.
  • Another object of the present invention is to achieve a communication system with an improved RF performance with regard to e.g. coverage, sensitivity and output power.
  • Another advantage of the invention is that is allows the user to change the output power and receiver sensitivity of the device.
  • Example one would be a not so price sensitive but RF coverage concerned user.
  • the invention might open up complete new user scenarios.
  • Another example is a user who is health risk concerned who wants to keep RF pollution away from human bodies and therefore appreciates lower output power or an antenna further away from critical body parts.
  • a third user might be more security oriented and does not want that other RF polluting devices are around the device; examples thereof are microwave ovens, mobile phones or other wireless devices. By locating the antenna further away and/ or changing the receiver sensitivity the wireless system can become more robust.
  • Figure 1 shows a system according to the state of the art.
  • Figure 2 shows coverage areas for different antennas.
  • Figure 3 shows a schematic block diagram of a radio communication system according to the present invention.
  • Figure 4 shows a refinement of the embodiment shown in figure 3.
  • Figure 5 shows an embodiment of the present invention.
  • Figure 6 shows an alternative embodiment of the present invention including a
  • Figure 7 shows a further alternative embodiment of the present invention also including a Bluetooth implementation.
  • Figure 3 shows a schematic block diagram of a radio communication system according to the present invention.
  • the radio communication system comprises a communication device 2, an internal radio frequency (RF) part 6 provided with an internal antenna 10 and a switch connector part 28 adapted to connect said internal RF part to the communication device.
  • the switch connector part 28 is placed between the RF part 6 and the main electronics of the device. It is connected to the communication device via a digital signal connection 4.
  • the communication system further comprises an external radio frequency (RF) station 17, including an external antenna means 16 and an external radio frequency (RF) part 34.
  • the external RF station is adapted to be connected to the switch connector part via a digital signal transmitting cable 32 that, when connected, transmits signals in digital form between the external RF station and the communication device 2 via the switch connector part 28.
  • the external RF station is located at a distance from said internal RF part in a location having different communication performance than the location of the internal RF part.
  • the external RF station 17 is adapted to receive and/or transmit RF information. Received RF information is amplified, demodulated and also A/D converted in the external RF part 34 prior transmitted to the communication device 2 via the digital signal transmitting cable and the connector part 28. Information to be transmitted by the communication device via the external RF station is received via the digital signal transmitting cable from the communication device in a digital form. It is then D/A converted, modulated and amplified in the external RF part prior transmitted by the external antenna.
  • the device 2 may be connected to its internal RF part 6 and the internal antenna 10.
  • the device may instead be connected to the external RF station 17.
  • the switch connector part 28 may be controlled in different ways.
  • the switch connector part 28 connects the internal RF part 6 to the communication device as long as the digital transmitting cable 32 is not connected to the connector part 28.
  • the connector 30 is connected to the connector part 28 the external RF station 17 instead is connected to the communication device.
  • the switch connector part 28 is adapted to connect either of the internal RF part or the external RF station depending on which for the moment exhibits the best transmitting and/ or receiving capabilities. This may be accomplished in the connector part by continuously measure the signal strength of the two RF parts.
  • the switch connector part 28 may be manually switched to use the external RF station or the internal RF part.
  • the external antenna means 16 may be placed on a better location, or has more preferable gain radiation characteristics such as directional gain instead of omnidirectional antenna gain radiation characteristics compared to the internal antenna.
  • the external RF part 34 may also have a higher receiver sensitivity or output power. For instance in a Bluetooth environment (see below), the coverage of the communication device 2 and its counterpart can be increased from 10m to 1000m.
  • Figure 2 shows a communication device 2 and its coverage area 22 showed with a solid line.
  • the coverage may increase to the area surrounded by the dotted line 24.
  • the coverage area may be changed into a non-omni-directional coverage area 26. The maximum distance increases.
  • Figure 4 is similar to Figure 3, it shows a communication device 2 with an antenna 10, a RF part 6 and a switch connector part 28.
  • the external RF part 36 has an increased receiver sensitivity and/ or higher output power, which is indicated by bold symbols for the amplifiers.
  • Figure 5 shows an embodiment of the present invention where the external RF station 17 comprises a RF diversity module 37.
  • the RF diversity module 37 is connected to at least two antennas 38 and 40. More antennas 42 are optional.
  • the RF diversity module 37 may comprise a relatively simple switching algorithm or include more sophisticated diversity mechanism on a lower, digital level. A coverage increase or a better bandwidth of the communication device 2 may then be achieved.
  • Figure 6 shows an alternative embodiment of the present invention where it is implemented in a Bluetooth environment.
  • the switch connector part 28 is placed between a Bluetooth internal RF part 6 and a digital Baseband module 46.
  • the internal RF part 6 may be e.g. a Bluetooth class 1 or class 2 radio, meaning that the output power is at maximum 0 dBm or 4dBm.
  • the external RF part 48 can be a class 1 radio, meaning that the output power can have up to 20 dBm. Since many Bluetooth Radio components are standardized, such a setup may be almost compatible without new and costly Baseband module 46 developments.
  • FIG. 7 shows a second alternative embodiment of the present invention also being a Bluetooth environment implementation.
  • This embodiment includes a baseband module 46 arranged between the connector part 56 and the internal RF part 6.
  • This embodiment includes also an external baseband module 50 in the external RF station 17.
  • the switch connector part 56 may disconnect the internal Baseband 46 from the device 2 and then connect the connector 58 via a digital cable 60 to the external RF station 62 as in the above-described embodiments.
  • Reference signs 4 and 44 designate digital signal connections.
  • the internal and external baseband modules 46 and 50 may include further functions and/ or may be an integral part of a more complex module, especially if it is integrated in one/two/three chip solutions, cost effective complete ICs.
  • the above shown figures focused on the increase of the coverage of the communication device 2.
  • the invention may be used to decrease the output power and therefore to reduce the health risks for the user.
  • the preferred location relates to minimizing the human RF exposure.

Landscapes

  • Transceivers (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)

Abstract

A radio communication system comprising a communication device (2), an internal radio frequency (RF) part (6) provided with an internal antenna (10) and a switch connector part (28) adapted to connect said internal RF part to the communication device. The system further comprises an external radio frequency (RF) station (17), including an external antenna means (16) and an external radio frequency (RF) part (34). The external RF station is adapted to be connected to the switch connector part via a digital signal transmitting cable (32) that, when connected, transmits signals in digital form between the external RF station and the communication device (2) via the switch connector part. the external RF station is located at a distance from said internal RF part in a location having different communication performance than the location of the internal RF part.

Description

Title
Radio communication system comprising an internal and an external antenna part connected via a digital signal transmitting cable
Field of the invention
The present invention relates to a communication system according to the preamble of the independent claim.
In particular the invention relates to radio communication devices and antenna systems thereof.
Background of the invention
The coverage of every radio communication is limited by the receiver sensitivity, the output power, the antenna gain radiation characteristics of the transmitting antenna, the antenna gain characteristics of the receiving antenna, the location of the transmitting antenna and the location of the receiving antenna. The fundamentals of radio propagation are described in the Friische Formulas.
In order to increase the coverage area of a radio device the above mentioned parameters must be improved. This invention is about taking all the above mentioned parameters into account, especially the antenna gain radiation characteristics of the transmitting antenna, the antenna gain characteristics of the receiving antenna, the location of the transmitting antenna and the location of the receiving antenna.
Short link radio devices are getting more and more popular. Mobile phones are becoming a more central point of the everyday life and many ongoing developments show that more and more electronic components/ devices will be connected with each other and especially with the Internet. Bluetooth, IEEE 802.11, hyperlan and homeRF are three examples of a variety of industrial efforts. This invention tries to expand the existing coverage of an RF system.
Further more it is obvious that there will always be a user scenario where users or machines are located outside the existing coverage area of a radio communication device.
The typical frequency bands of the invention are between lOOMHz up to 20 GHz. US-5,828,341 discloses a laptop computer having an internal radio with interchangeable antenna features. In this known device a switch is provided, arranged to selectively connect the communication device with one of the dedicated antenna and the external antenna. The external antenna is connected to the communication device via an RF cable, e.g. a coaxial cable.
US-5,930,728 addresses the problem in a 1900 MHz communication system when an antenna is placed in an attic or other raised elevation a large coaxial cable must be used to carry a 1900 MHz signal as a result of cable attenuation resulting from these frequencies. By "large" is meant a cable with approximately a % inch diameter. In this known device using a lower frequency, e.g. 900 MHz, having lower attenuation in the cable, solves the above-mentioned attenuation problem. A smaller diameter coaxial cable may then be used.
As indicated in US-5,930,728 one main drawback of the state of the art is the loss inside a coaxial cable. The typical values are several dBs per 10m of cable. Especially the frequency bands of the future, e.g. 2.4GHZ, 5.6 GHz will be limited to a very short cable length. In other words: The improved RF location on the roof of a car has to be paid by a RF cable with high attenuation losses, in certain applications the losses equalize the gained RF performance and make the external antenna practically useless.
Another disadvantage is that the state of the art is limited to one RF part with a certain receiver sensitivity and output power. Even if some users would agree to pay the costs for a more sophisticated RF performance, the price/ dB ratio is always adjusted to the bulk of users and their demands and cost demands.
Figure 1 shows a system according to the state of the art. A communication device 2 is communicating or receiving information from another communication device (not shown). The device has an antenna 10, fixed to the device 2, an RF part 6 and a switch connector part 8. A connector 12 is adapted to be connected to the connector switch 8. When the connector 12 is connected to the switch connector the RF transmission line 14, e.g. a coaxial cable, connects the external antenna 16 with the RF part 6. The internal antenna 10 is then switched off.
A typical example of the state of the art is a TV with an internal TV antenna. Usually the coverage is not sufficient inside homes. Therefore an external directional antenna, mounted on the roof of the house is connected via a coaxial cable to the TV.
Another example is a mobile phone used inside a car. A coaxial cable is connecting an external antenna, mounted outside the car, with the mobile phone. Once the external antenna is connected into the mobile phone the mobile phone antenna gets switched off. The coverage increases resulting in less dropped calls.
The object of the present invention is to overcome the above-mentioned drawback in prior art systems related to the attenuation in coaxial cables, especially in high frequency systems.
Another object of the present invention is to achieve a communication system with an improved RF performance with regard to e.g. coverage, sensitivity and output power.
Summary of the invention
The above-mentioned objects are achieved by the communication system set forth in characterizing part of the independent claim.
Preferred embodiments are set forth in the dependent claims.
It is an advantage of the invention that no RF performance loss occurs with the usage of a digital signal transmission cable. Of course even for those cables a distance limit exists, but as long the system operates below this limit no decrease of the coverage occurs.
Another advantage of the invention is that is allows the user to change the output power and receiver sensitivity of the device. Example one would be a not so price sensitive but RF coverage concerned user. For him the invention might open up complete new user scenarios. Another example is a user who is health risk concerned who wants to keep RF pollution away from human bodies and therefore appreciates lower output power or an antenna further away from critical body parts.
A third user might be more security oriented and does not want that other RF polluting devices are around the device; examples thereof are microwave ovens, mobile phones or other wireless devices. By locating the antenna further away and/ or changing the receiver sensitivity the wireless system can become more robust.
Short description of the appended drawings Figure 1 shows a system according to the state of the art. Figure 2 shows coverage areas for different antennas.
Figure 3 shows a schematic block diagram of a radio communication system according to the present invention.
Figure 4 shows a refinement of the embodiment shown in figure 3. Figure 5 shows an embodiment of the present invention. Figure 6 shows an alternative embodiment of the present invention including a
Bluetooth implementation.
Figure 7 shows a further alternative embodiment of the present invention also including a Bluetooth implementation.
Detailed description of preferred embodiments of the invention
Figure 3 shows a schematic block diagram of a radio communication system according to the present invention.
The radio communication system comprises a communication device 2, an internal radio frequency (RF) part 6 provided with an internal antenna 10 and a switch connector part 28 adapted to connect said internal RF part to the communication device. The switch connector part 28 is placed between the RF part 6 and the main electronics of the device. It is connected to the communication device via a digital signal connection 4. The communication system further comprises an external radio frequency (RF) station 17, including an external antenna means 16 and an external radio frequency (RF) part 34. The external RF station is adapted to be connected to the switch connector part via a digital signal transmitting cable 32 that, when connected, transmits signals in digital form between the external RF station and the communication device 2 via the switch connector part 28. The external RF station is located at a distance from said internal RF part in a location having different communication performance than the location of the internal RF part.
Different possible locations for the external RF station may be where it is possible to arrange the external antenna means in order to achieve optimal transmitting performance, e.g. outside a car and at a roof of a building. The external RF station 17 is adapted to receive and/or transmit RF information. Received RF information is amplified, demodulated and also A/D converted in the external RF part 34 prior transmitted to the communication device 2 via the digital signal transmitting cable and the connector part 28. Information to be transmitted by the communication device via the external RF station is received via the digital signal transmitting cable from the communication device in a digital form. It is then D/A converted, modulated and amplified in the external RF part prior transmitted by the external antenna.
If during the usage of the device the coverage is sufficient, the device 2 may be connected to its internal RF part 6 and the internal antenna 10.
If the coverage is not sufficient, the device may instead be connected to the external RF station 17.
The switch connector part 28 may be controlled in different ways.
According to a first preferred embodiment of the present invention the switch connector part 28 connects the internal RF part 6 to the communication device as long as the digital transmitting cable 32 is not connected to the connector part 28. When the connector 30 is connected to the connector part 28 the external RF station 17 instead is connected to the communication device.
According to a second preferred embodiment of the present invention the switch connector part 28 is adapted to connect either of the internal RF part or the external RF station depending on which for the moment exhibits the best transmitting and/ or receiving capabilities. This may be accomplished in the connector part by continuously measure the signal strength of the two RF parts.
According to a third preferred embodiment of the present invention the switch connector part 28 may be manually switched to use the external RF station or the internal RF part.
The external antenna means 16 may be placed on a better location, or has more preferable gain radiation characteristics such as directional gain instead of omnidirectional antenna gain radiation characteristics compared to the internal antenna. The external RF part 34 may also have a higher receiver sensitivity or output power. For instance in a Bluetooth environment (see below), the coverage of the communication device 2 and its counterpart can be increased from 10m to 1000m.
Figure 2 shows a communication device 2 and its coverage area 22 showed with a solid line. By increasing the receiver sensitivity, or the output power or the antenna efficiency the coverage may increase to the area surrounded by the dotted line 24. Via the usage of a directional antenna the coverage area may be changed into a non-omni-directional coverage area 26. The maximum distance increases.
Figure 4 is similar to Figure 3, it shows a communication device 2 with an antenna 10, a RF part 6 and a switch connector part 28. The external RF part 36 has an increased receiver sensitivity and/ or higher output power, which is indicated by bold symbols for the amplifiers.
Figure 5 shows an embodiment of the present invention where the external RF station 17 comprises a RF diversity module 37. The RF diversity module 37 is connected to at least two antennas 38 and 40. More antennas 42 are optional. The RF diversity module 37 may comprise a relatively simple switching algorithm or include more sophisticated diversity mechanism on a lower, digital level. A coverage increase or a better bandwidth of the communication device 2 may then be achieved. Figure 6 shows an alternative embodiment of the present invention where it is implemented in a Bluetooth environment. The switch connector part 28 is placed between a Bluetooth internal RF part 6 and a digital Baseband module 46. The internal RF part 6 may be e.g. a Bluetooth class 1 or class 2 radio, meaning that the output power is at maximum 0 dBm or 4dBm. The external RF part 48 can be a class 1 radio, meaning that the output power can have up to 20 dBm. Since many Bluetooth Radio components are standardized, such a setup may be almost compatible without new and costly Baseband module 46 developments.
Figure 7 shows a second alternative embodiment of the present invention also being a Bluetooth environment implementation. This embodiment includes a baseband module 46 arranged between the connector part 56 and the internal RF part 6. This embodiment includes also an external baseband module 50 in the external RF station 17. The switch connector part 56 may disconnect the internal Baseband 46 from the device 2 and then connect the connector 58 via a digital cable 60 to the external RF station 62 as in the above-described embodiments. Reference signs 4 and 44 designate digital signal connections. Obviously, the internal and external baseband modules 46 and 50 may include further functions and/ or may be an integral part of a more complex module, especially if it is integrated in one/two/three chip solutions, cost effective complete ICs.
The above shown figures focused on the increase of the coverage of the communication device 2. In certain applications it might be useful to decrease the coverage or to decrease RF pollution in the close surrounding of the device 2. Further more some users might be worried about the health effects of the RF radiation, then the invention may be used to decrease the output power and therefore to reduce the health risks for the user. In this case the preferred location relates to minimizing the human RF exposure.
The present invention is not limited to the above-described preferred embodiments. Various alternatives, modifications and equivalents may be used. Therefore, the above embodiments should not be taken as limiting the scope of the invention, which is defined by the appending claims.

Claims

Claims
1. A radio communication system comprising a communication device (2), an internal radio frequency (RF) part (6) provided with an internal antenna (10) and a switch connector part (28) adapted to connect said internal RF part to the communication device, characterized in that the system further comprises an external radio frequency (RF) station (17), including an external antenna means (16) and an external radio frequency (RF) part (34), said external RF station is adapted to be connected to the switch connector part via a digital signal transmitting cable (32) that, when connected, transmits signals in digital form between the external RF station and the communication device (2) via the switch connector part.
2. Communication system according to claim 1, characterized in that the switch connector part is adapted to connect the external RF station or the internal RF part to the communication device (2).
3. Communication system according to claims 1 or 2, characterized i n that the communication device may transmit or receive information via the external RF station if the digital signal transmitting cable is connected to the switch connector part.
4. Communication system according to claims 1 or 2, characterized i n that the switching of the switch connector part is controlled in dependence of the communication performance of the different locations.
5. Communication system according to claims 1 or 2, characterized i n that the switching of the switch connector part is manually controlled.
6. Communication system according to any preceding claims, characterized in that said external RF station comprises an RF diversity module (37) adapted to connect one of at least two antennas (38, 40) arranged in said external antenna means.
7. Communication system according to any preceding claims, characterized in that said system is arranged to transmit and/ or receive radio frequency information using the Bluetooth protocol.
8. Communication system according to claim 7, c h a r a c t e r i z e d in that a Bluetooth baseband module (46) is arranged between said switch connector part (28) and the communication device (2).
9. Communication system according to claim 7, c h a r a c t e r i z e d in that a Bluetooth baseband module (50) is arranged in said external RF station (62).
10. Communication system according to any preceding claim, characterized in that the external RF station is located at a distance from said internal RF part in a location having different communication performance than the location of the internal RF part.
PCT/SE2002/000090 2001-01-22 2002-01-21 Radio communication system comprising an internal and an external antenna part connected via a digital signal transmitting cable WO2002058282A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE0100165A SE0100165D0 (en) 2001-01-22 2001-01-22 Communication system
SE0100165-0 2001-01-22

Publications (1)

Publication Number Publication Date
WO2002058282A1 true WO2002058282A1 (en) 2002-07-25

Family

ID=20282680

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE2002/000090 WO2002058282A1 (en) 2001-01-22 2002-01-21 Radio communication system comprising an internal and an external antenna part connected via a digital signal transmitting cable

Country Status (2)

Country Link
SE (1) SE0100165D0 (en)
WO (1) WO2002058282A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008118060A1 (en) * 2007-03-27 2008-10-02 Proant Ab Antenna selection switch
CN114089053A (en) * 2021-08-12 2022-02-25 山东德源电力科技股份有限公司 All-round type HPLC module tester

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10233724A (en) * 1997-02-20 1998-09-02 Kokusai Electric Co Ltd Wireless relay system
JPH11112376A (en) * 1997-09-30 1999-04-23 Mitsumi Electric Co Ltd Satellite broadcast reception system
US5930728A (en) * 1996-08-29 1999-07-27 Ericsson Inc. Up converted home base station
JP2000341744A (en) * 1999-05-27 2000-12-08 Ntt Docomo Inc Wireless device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5930728A (en) * 1996-08-29 1999-07-27 Ericsson Inc. Up converted home base station
JPH10233724A (en) * 1997-02-20 1998-09-02 Kokusai Electric Co Ltd Wireless relay system
JPH11112376A (en) * 1997-09-30 1999-04-23 Mitsumi Electric Co Ltd Satellite broadcast reception system
JP2000341744A (en) * 1999-05-27 2000-12-08 Ntt Docomo Inc Wireless device

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008118060A1 (en) * 2007-03-27 2008-10-02 Proant Ab Antenna selection switch
CN114089053A (en) * 2021-08-12 2022-02-25 山东德源电力科技股份有限公司 All-round type HPLC module tester

Also Published As

Publication number Publication date
SE0100165D0 (en) 2001-01-22

Similar Documents

Publication Publication Date Title
CN111193526B (en) Radio frequency system and electronic equipment
CN111327344B (en) Radio frequency system and electronic equipment
US6507322B2 (en) Space diversity slot antennas and apparatus using the same
US6006117A (en) Radio telephone with separate antenna for stand-by mode
CN108462498B (en) Multiplexer switches, radio frequency systems and wireless communication equipment
JPH07111485A (en) Radio transmission method
JP2002033691A (en) Active reflector and wireless data communication system
JP4425711B2 (en) Antenna control method and radio transmission / reception apparatus
US20140153493A1 (en) Sector-based base station
US7796955B2 (en) Expandable wireless transceiver
JP2002009679A (en) Wireless terminal
EP1124337A2 (en) Switchless half-duplex transceiver front end
US10091742B2 (en) Wireless communication device
KR20130048553A (en) Wifi module with interior and exterior antenna
US7010335B2 (en) Apparatus and method to provide antenna diversity
WO2002058282A1 (en) Radio communication system comprising an internal and an external antenna part connected via a digital signal transmitting cable
US6697021B2 (en) Double F antenna
KR100886678B1 (en) Wireless internet access system
CN101312356A (en) Expandable wireless signal transceiver
CN1832249B (en) Impedance transformation in a duplexer using a transmission line
JPH07154314A (en) Local radio communication network
US12425080B2 (en) Wireless communication system
FI81932C (en) TVAODELAD RADIO TELEPHONE.
JP2013197636A (en) Radio communication type portable tv tuner
KR100222797B1 (en) Structure of broadband center loading antenna

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SD SE SG SI SK SL TJ TM TN TR TT TZ UA UG US UZ VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 69(1) EPC OF 311003

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

WWW Wipo information: withdrawn in national office

Country of ref document: JP