CA2275251A1 - Wireless communications station and system - Google Patents
Wireless communications station and system Download PDFInfo
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- CA2275251A1 CA2275251A1 CA002275251A CA2275251A CA2275251A1 CA 2275251 A1 CA2275251 A1 CA 2275251A1 CA 002275251 A CA002275251 A CA 002275251A CA 2275251 A CA2275251 A CA 2275251A CA 2275251 A1 CA2275251 A1 CA 2275251A1
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- communications
- wireless communications
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- networks
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
- H04W88/08—Access point devices
- H04W88/085—Access point devices with remote components
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/24—Radio transmission systems, i.e. using radiation field for communication between two or more posts
- H04B7/26—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
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- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Mobile Radio Communication Systems (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
A wireless communications station comprising a base unit (10) comprising of communications interface for communicating with plural wireless networks, a received communications combiner (12) for combining received signals from plural wireless communications networks into plural radio frequency outputs, at least one fiberoptic transmitter (14) receiving the single radio frequency output and providing optical output (16) and at least one fiberoptic receiver (22) for receiving optical signals and providing RF output, a plurality of remote units (20), each including plural antennas (220) for communicating with wireless communications networks and a received communications splitter (24) for splitting combined received communications signals from base unit and a transmit communications combiner (12) for combining transmit communications signals.
Description
WO 98!27748 PCT/11,97/00411 WIRELESS CO1~IMUNICATIONS STATION AND SYSTEM
FIE~:LD OF THE I7VVENTION
The present invention relates to communications systems generally and more particularly to wireless communications systems employing optical fibers.
BACKGROUND OF TILE INVENTION
Cellular radio was conceived to provide high capacity mobile communications without requiring large amounts of spectrum. The original concept as proposed by AT&T, involves the use of a frequency band within a region known as a cell and reusing the same frequency band in other adjacent cells with manageable interference between cells.
to The capacity of a cellular radio nfawork increases as the number of cells increases with decreasing cell size. The small cells are known as microcells.
Optical fibers have been used to feed the RF signal to microcells. Optical fiber can be run inside buildings, train stations, malls, etc. to improve coverage in a wireless communications system.
United States Patent 5,457,357 describes a number of details of a fiber optic is microceliular radio system.
Present day wireless communications systems may be divided into a number of groups. These include cellular telephone networka, cordless telephones, wide area data networks, wireless local area networks, paging/messaging and satellite mobile systems. Each wireless communications system has its own frequen<:y band and modulation scheme as well as 2o its own geographic location in which the system i:; deployed. Some of these systems may become obsolete while others may evolve into future personal communication systems.
Nevertheless, it appears that two or more wireless systems will commonly be found in any location.
Conventionally, each wireless communications system has its own network for 25 improved coverage in buildings and other shadowed areas. A building which requires improved coverage for more than one wireless service must be "wired" separately for each service.
SU~IARY OF THE INVENTION
The present invention seeks to provide an improved distributed antenna network for microcells. The present invention further seeks to provide a single optical fiber 3o network which is used simultaneously for a number of wireless communications systems.
There is thus provided in accordance with a preferred embodiment of the present invention a wireless communications station comprising:
a base unit including:
WO 98/27748 PCT/8.97/00411 a communications interface for communicating with plural wireless communications networks;
a received communications combiner for combining received communications signals received from the plural wireless communications networks into a single radio frequency output;
a transmit communications splitter for splitting previously combined transmit communications signals to be transmitted to the plural wireless communications networks into plural radio frequency outputs;
at least one fiberoptic transmitter receiving the single radio frequency l0 output and providing a corresponding optical output; and at least one fiberoptic receiver receiving an optical input and providing an RF output containing previously combined transmit communications signals;
a plurality of remote units, each including:
plural antennas for communicating with communicators along plural wireless communications networks;
a received communications splitter for splitting previously combined received communications signals from the base unit and supplying them to the plural antennas;
a transmit communications combiner for combining transmit communications signals from the plural antennas into a combined radio frequency output;
2o a fiberoptic transmitter receiving the combined radio frequency output and providing a corresponding optical output; and a fiberoptic receiver receiving an optical input and providing an RF
output to the received communications splitter containing previously received transmit communications signals;
a first optical fiber connecting each fiberoptic transmitter of the base unit with a corresponding fiberoptic receiver in a corresponding remote unit; and a second optical fiber connecting each fiberoptic transmitter of a remote unit with a corresponding fiberoptic receiver in the base unit.
Preferably each remote unit also comprises a diplexer or other isolation apparatus interposed between each of the plural antennas and the combiner and the splitter, so as to enable simultaneous two way communications via each antenna at different frequencies for transmission and reception.
WO 98!27748 PCT/)Z.97/00411 Preferably the plural wireless communications networks include at least two communications networks selected from the group consisting of cellular telephone networks, cordless telephones, wide area data networks, wireless local area networks, personal communications systems, personal communications networks, paging/messaging networks and satellite mobile systems.
In accordance with a preferred embodiment of the present invention, a low frequency control signal is multiplexed by the communications interface onto the fiber network for providing loop back alarm status of each remote unit and to provide control signals thereto, which control amplifier gain thereof 1o In accordance with a preferred embodiment of the present invention, the plural antennas include at last one swivel mounted directional antenna whose direction may be adjusted on site.
Preferably, the base unit also includea tuning circuitry which permits dynamic tuning and transmission/reception balance of cell size of each of the remote units.
The base unit may also include a network management interface which allows monitoring of the operational status of a base unit and the remote units connected thereto.
Preferably, the fiberoptic transmitter employs a vertical cavity surface emitting laser or an edge emitting laser coupled to a single or multi mode fiber. The edge emitting laser may be a distributed feedback laser integrated with an optical isolator.
2o There is additionally provided in accordance with a preferred embodiment of the present invention a microcellular telecommunications system employing a fiber network including optical fibers which may be single or multi mode and optical transmitters for transmitting signals along the optical fibers) the optical transmitters comprising a vertical cavity surface emitting laser.
BRIEF DESCRIPTION OF 'THE DRAWINGS
The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:
Fig. I is a simplified pictorial illustration of part of a wireless communications station, constructed and operative in accordance wil:h a preferred embodiment of the present invention;
Fig. 2 is a simplified block diagram illustration of circuitry employed in the apparatus of Fig. 1;
WO 98/27748 PCT/8.97/00411 Fig. 3 is a somewhat more detailed block diagram illustration of part of the circuitry of Fig. 2;
Fig. 4 is a simplified block diagram illustration of a soft limiter, constructed and operative in accordance with a preferred embodiment of the present invention.
Fig. SA is a simplified block diagram of part of the circuitry of Fig. 2, in accordance with a preferred embodiment of the present invention;
Fig. SB is a simplified block diagram of part of the circuitry of Fig. 2, in accordance with another preferred embodiment of the present invention, and including microprocessor control of remote antenna units;
to Fig. SC is a simplified illustration of a remote control unit for remotely con-trolling control parameters of a local cell, in accordance with a preferred embodiment of the present invention;
Fig. 6 is a simplified block diagram illustration of network management apparatus useful in the apparatus of Figs. 1 - SB; and Fig. 7 is an illustration of the use of directional antennas in a system of the type illustrated in Figs. 1 - 6.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
Reference is now made to Figs. 1 and 2, which illustrate a multi-system station which forms part of a wireless communications system constructed and operative in 2o accordance with a preferred embodiment of the present invention.
In a typical system a plurality of wireless network services, such as PCS, GSM
and other wireless telephone and radio services as well as paging services, each communicate via an appropriate antenna (not shown) with one or more multi-system stations such as that illustrated in Fig. 1. Each station may be a building, part of a building or a plurality of buildings, depending upon system requirements.
In accordance with a preferred embodiment of the present invention, each station comprises a base unit 10 which communicates with each of the required wireless network services, typically via wide bandwidth RF interface wired links which provide, typically a GSM input, a GSM output, a PCS input, a PCS output and a paging input. It is 3o appreciated that any other suitable systems may also be connected to the base unit 10.
As seen in Fig. 2, the base unit 10 preferably comprises an input combiner 12, which combines the various wireless inputs, such as the GSM, PC S and paging inputs into a combined output, typically in the form of a multiplexed signal, and provides the multiplexed WO 98/27748 PCT/8.97/00411 signal via respective fiberoptic transmitters 14 and fiberoptic cables 16 to a plurality of remote units 20, which are typically distributed on different floors, or even in different rooms of one or more buildings or any indoor or shadowed areas, depending on the building construction and system requirements.
FIE~:LD OF THE I7VVENTION
The present invention relates to communications systems generally and more particularly to wireless communications systems employing optical fibers.
BACKGROUND OF TILE INVENTION
Cellular radio was conceived to provide high capacity mobile communications without requiring large amounts of spectrum. The original concept as proposed by AT&T, involves the use of a frequency band within a region known as a cell and reusing the same frequency band in other adjacent cells with manageable interference between cells.
to The capacity of a cellular radio nfawork increases as the number of cells increases with decreasing cell size. The small cells are known as microcells.
Optical fibers have been used to feed the RF signal to microcells. Optical fiber can be run inside buildings, train stations, malls, etc. to improve coverage in a wireless communications system.
United States Patent 5,457,357 describes a number of details of a fiber optic is microceliular radio system.
Present day wireless communications systems may be divided into a number of groups. These include cellular telephone networka, cordless telephones, wide area data networks, wireless local area networks, paging/messaging and satellite mobile systems. Each wireless communications system has its own frequen<:y band and modulation scheme as well as 2o its own geographic location in which the system i:; deployed. Some of these systems may become obsolete while others may evolve into future personal communication systems.
Nevertheless, it appears that two or more wireless systems will commonly be found in any location.
Conventionally, each wireless communications system has its own network for 25 improved coverage in buildings and other shadowed areas. A building which requires improved coverage for more than one wireless service must be "wired" separately for each service.
SU~IARY OF THE INVENTION
The present invention seeks to provide an improved distributed antenna network for microcells. The present invention further seeks to provide a single optical fiber 3o network which is used simultaneously for a number of wireless communications systems.
There is thus provided in accordance with a preferred embodiment of the present invention a wireless communications station comprising:
a base unit including:
WO 98/27748 PCT/8.97/00411 a communications interface for communicating with plural wireless communications networks;
a received communications combiner for combining received communications signals received from the plural wireless communications networks into a single radio frequency output;
a transmit communications splitter for splitting previously combined transmit communications signals to be transmitted to the plural wireless communications networks into plural radio frequency outputs;
at least one fiberoptic transmitter receiving the single radio frequency l0 output and providing a corresponding optical output; and at least one fiberoptic receiver receiving an optical input and providing an RF output containing previously combined transmit communications signals;
a plurality of remote units, each including:
plural antennas for communicating with communicators along plural wireless communications networks;
a received communications splitter for splitting previously combined received communications signals from the base unit and supplying them to the plural antennas;
a transmit communications combiner for combining transmit communications signals from the plural antennas into a combined radio frequency output;
2o a fiberoptic transmitter receiving the combined radio frequency output and providing a corresponding optical output; and a fiberoptic receiver receiving an optical input and providing an RF
output to the received communications splitter containing previously received transmit communications signals;
a first optical fiber connecting each fiberoptic transmitter of the base unit with a corresponding fiberoptic receiver in a corresponding remote unit; and a second optical fiber connecting each fiberoptic transmitter of a remote unit with a corresponding fiberoptic receiver in the base unit.
Preferably each remote unit also comprises a diplexer or other isolation apparatus interposed between each of the plural antennas and the combiner and the splitter, so as to enable simultaneous two way communications via each antenna at different frequencies for transmission and reception.
WO 98!27748 PCT/)Z.97/00411 Preferably the plural wireless communications networks include at least two communications networks selected from the group consisting of cellular telephone networks, cordless telephones, wide area data networks, wireless local area networks, personal communications systems, personal communications networks, paging/messaging networks and satellite mobile systems.
In accordance with a preferred embodiment of the present invention, a low frequency control signal is multiplexed by the communications interface onto the fiber network for providing loop back alarm status of each remote unit and to provide control signals thereto, which control amplifier gain thereof 1o In accordance with a preferred embodiment of the present invention, the plural antennas include at last one swivel mounted directional antenna whose direction may be adjusted on site.
Preferably, the base unit also includea tuning circuitry which permits dynamic tuning and transmission/reception balance of cell size of each of the remote units.
The base unit may also include a network management interface which allows monitoring of the operational status of a base unit and the remote units connected thereto.
Preferably, the fiberoptic transmitter employs a vertical cavity surface emitting laser or an edge emitting laser coupled to a single or multi mode fiber. The edge emitting laser may be a distributed feedback laser integrated with an optical isolator.
2o There is additionally provided in accordance with a preferred embodiment of the present invention a microcellular telecommunications system employing a fiber network including optical fibers which may be single or multi mode and optical transmitters for transmitting signals along the optical fibers) the optical transmitters comprising a vertical cavity surface emitting laser.
BRIEF DESCRIPTION OF 'THE DRAWINGS
The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:
Fig. I is a simplified pictorial illustration of part of a wireless communications station, constructed and operative in accordance wil:h a preferred embodiment of the present invention;
Fig. 2 is a simplified block diagram illustration of circuitry employed in the apparatus of Fig. 1;
WO 98/27748 PCT/8.97/00411 Fig. 3 is a somewhat more detailed block diagram illustration of part of the circuitry of Fig. 2;
Fig. 4 is a simplified block diagram illustration of a soft limiter, constructed and operative in accordance with a preferred embodiment of the present invention.
Fig. SA is a simplified block diagram of part of the circuitry of Fig. 2, in accordance with a preferred embodiment of the present invention;
Fig. SB is a simplified block diagram of part of the circuitry of Fig. 2, in accordance with another preferred embodiment of the present invention, and including microprocessor control of remote antenna units;
to Fig. SC is a simplified illustration of a remote control unit for remotely con-trolling control parameters of a local cell, in accordance with a preferred embodiment of the present invention;
Fig. 6 is a simplified block diagram illustration of network management apparatus useful in the apparatus of Figs. 1 - SB; and Fig. 7 is an illustration of the use of directional antennas in a system of the type illustrated in Figs. 1 - 6.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
Reference is now made to Figs. 1 and 2, which illustrate a multi-system station which forms part of a wireless communications system constructed and operative in 2o accordance with a preferred embodiment of the present invention.
In a typical system a plurality of wireless network services, such as PCS, GSM
and other wireless telephone and radio services as well as paging services, each communicate via an appropriate antenna (not shown) with one or more multi-system stations such as that illustrated in Fig. 1. Each station may be a building, part of a building or a plurality of buildings, depending upon system requirements.
In accordance with a preferred embodiment of the present invention, each station comprises a base unit 10 which communicates with each of the required wireless network services, typically via wide bandwidth RF interface wired links which provide, typically a GSM input, a GSM output, a PCS input, a PCS output and a paging input. It is 3o appreciated that any other suitable systems may also be connected to the base unit 10.
As seen in Fig. 2, the base unit 10 preferably comprises an input combiner 12, which combines the various wireless inputs, such as the GSM, PC S and paging inputs into a combined output, typically in the form of a multiplexed signal, and provides the multiplexed WO 98/27748 PCT/8.97/00411 signal via respective fiberoptic transmitters 14 and fiberoptic cables 16 to a plurality of remote units 20, which are typically distributed on different floors, or even in different rooms of one or more buildings or any indoor or shadowed areas, depending on the building construction and system requirements.
5 Each remote unit 20 typically comprises a fiberoptic receiver 22 which receives the combined output, which is typically an RF output, and supplies it to a splitter 24 which is connected to individual antennas, such as antennas 30, 28 and 26 for PCS, GSM
and paging networks respectively. Each of antennas 26, 28 and 30 preferably has at least one external antenna connection. The splitter divides the combined output into individual output signals, 1o such as, for example, PCS, GSM and paging signals which are sent to respective antennas 30, 28 and 26.
Antennas 26, 28 and 30 transmit signals received via combiner 12, transmitters 14, optical fibers 16, receivers 22, and splitters :?4 to subscriber units such as cellular telephones 32 and pagers 34 (Fig. 1).
In each remote unit 20, antennas 26, 28 and 30 preferably operate in a full duplex mode and also receive signals from subscrilber units such as cellular telephones 32 operating on one or more networks, such as, for example, GSM and PCS networks.
These signals are supplied to a combiner 42 which combines the various wireless signal inputs, such as the GSM and PCS signals, into a combined output, typically in the form of a multiplexed 2o signal, and provides the multiplexed signal via a fiberc~ptic transmitter 44 and a fiberoptic cable 46 to base unit 10. Base unit 10 typically comprises a plurality of fiberoptic receivers 48, each corresponding to one of remote units 20, which receive the combined signal over fiberoptic cable 46 and supply it to an output sputter 50, which :splits the combined signal into a plurality of individual signal outputs, such as, for example, a GSM output and a PCS
output.
Reference is now made to Fig. 3 which illustrates the circuitry of the base unit 10 in somewhat more detail, showing typical input signal levels and frequency bands of the various input signals to the base unit. It is seen that the fiber optics transmitter typically comprises a laser diode 60. Preferably the transmitter 14 employs a vertical cavity surface emitting laser or an edge emitting laser coupled to a single or mufti-mode fiber 16.
3o Preferably each fiberoptic receiver 48 comprises a photodiode 62 which converts the optical signal to RF. A 10 KHz detector fi4 detects and filters out a 10 KHz tone.
If the 10 KHz tone is not detected, this is an indication of a break in the communications link and detector 64 causes illumination of a pilot LED 66. Another indication of a break in the WO 98/27748 PCT/a,97/00411 communications link is the absence of received light, which may be indicated by an optical alarm 68.
Reference is now made to Fig. 4 which illustrates a soft limiter 100, constructed and operative in accordance with a preferred embodiment of the present invention. At the uplink, one or more mobile telephones situated very close to the remote antenna may overdrive laser diode 60. Soft limiter 100 may be used at the uplink to prevent laser diode 60 from being overdriven, and thereby prevent non-linear distortion in all of the services distributed. At the downlink, soft limiter 100 protects any of the wireless services from inadvertently increasing input power to base unit 10.
to Soft limiter 100 preferably includes a switched attenuator 102, a comparator 104 and an RF power Level detector 106, as shown in Fig. 4.
Reference is now made to Fig. SA which is a block diagram of part of the circuitry of Fig. 2. There are a number of options of antenna communications with the communications system of the present invention. At the uplink portion of the communications system, jumpers may be used to connect the GSM antenna 28 and the PCS antenna 30 to local and/or remote antennas. Specifically, a jumper 70 may be used to connect GSM
antenna 28 solely to an internal antenna 72. An additional jumper 72 may be used to connect GSM
antenna 28 to a local antenna 76, which is preferably the same internal antenna 72, and to a remote antenna 78. Remote antenna 78 preferably is DC powered to allow for amplification 2o and may be connected by coax. Local antenna 76 and remote antenna 78 are preferably connected via a power divider/combiner 80. The foregoing description applies equally for PCS
antenna 30, as shown in Fig. SA.
The signals from each GSM antenna 28 and PCS antenna 30 are each input to a low noise amplifier (LNA) 82 via an antenna duplexer 84 in order to enable the same antenna to be used for transmission and reception. The signals from both the GSM
antenna 28 and PCS
antenna 30 are combined by combiner 42 and input to fiberoptic transmitter 44.
At the downlink, the optical signal from base unit 10 is amplified and demultiplexed by a demultiplexer 85. Preferably three signals are demultiplexed. A 10 KHz tone is input to transmitter 44, a low frequency paging signal is input to paging loop antenna 26, and an RF signal, comprising combined GSM and PCS signals, is input to a demultiplexer 86. These signals are each input to their respective antenna via antenna duplexer 84.
WO 98/27748 PCT/8.97/00411 As seen in Fig. SA, a gain control is provided at receiver 22 and transmitter 44.
The gain level is controlled by the amplitude of the 10 KHz pilot tone. The simultaneous gain control of the transmitted and received signals deternnines the size of the local cell.
Reference is now made to Fig. 5B which illustrates microprocessor control of remote units 20. Instead of analog control using the 10 KHz tone, a low frequency data signal may be multiplexed by a multiplexer 90 along with the RF signal. A
microprocessor 92 at each remote unit 20 receives the signal. The absence of l:he signal indicates an alarm status which microprocessor 92 relays to a microprocessor (not shown) at base unit 10. The low frequency data signal may be used for status and control of remote unit 20, and may include the following to control parameters:
a. Cell size: This controls gains of the transmitted and received signals b. Balance between transmitted and received signals c. Threshold of soft limiter 100.
Control parameters may be from base unit 10 or remotely controlled through a network management interface. However, it is sometiames more convenient to set these control parameters locally while the unit is tested in situ. Reference is now made to Fig. SC which illustrates a remote control unit 110 for remotely controlling control parameters of a local cell, in accordance with a preferred embodiment of the present invention. Remote control unit 110 preferably includes a plurality of control buttons, such as a cell size control button 112 and a 2o balance control button 114. For example, control button 112 may control volume, while control button 114 may control transmit cell balance, such as stereo balance.
An additional control button 116 may be provided for controlling threshold of soft limiter 100.
Reference is now made to Fig. 6, which is a simplified block diagram illustration of network management apparatus useful in the apparatus of Figs. I - SC. The network management apparatus typically comprises a microprocessor 200 which communicates typically via an RS 232 interface 202 and a modem 204 with an external communications network such as an ordinary telephone network. The microprocessor receives status indications from alarm indicators 206 which indicate malfunctions in remote units 20 (Fig. 1 ) based on receipt of loop back signals therefrom.
3o Microprocessor 200 provides gain conl:ro) signals to the remote units via a D/A
converter 208 and a loop back signal generator :210. Loop back signal generator 210 preferably operates at approximately 10 KHz.
and paging networks respectively. Each of antennas 26, 28 and 30 preferably has at least one external antenna connection. The splitter divides the combined output into individual output signals, 1o such as, for example, PCS, GSM and paging signals which are sent to respective antennas 30, 28 and 26.
Antennas 26, 28 and 30 transmit signals received via combiner 12, transmitters 14, optical fibers 16, receivers 22, and splitters :?4 to subscriber units such as cellular telephones 32 and pagers 34 (Fig. 1).
In each remote unit 20, antennas 26, 28 and 30 preferably operate in a full duplex mode and also receive signals from subscrilber units such as cellular telephones 32 operating on one or more networks, such as, for example, GSM and PCS networks.
These signals are supplied to a combiner 42 which combines the various wireless signal inputs, such as the GSM and PCS signals, into a combined output, typically in the form of a multiplexed 2o signal, and provides the multiplexed signal via a fiberc~ptic transmitter 44 and a fiberoptic cable 46 to base unit 10. Base unit 10 typically comprises a plurality of fiberoptic receivers 48, each corresponding to one of remote units 20, which receive the combined signal over fiberoptic cable 46 and supply it to an output sputter 50, which :splits the combined signal into a plurality of individual signal outputs, such as, for example, a GSM output and a PCS
output.
Reference is now made to Fig. 3 which illustrates the circuitry of the base unit 10 in somewhat more detail, showing typical input signal levels and frequency bands of the various input signals to the base unit. It is seen that the fiber optics transmitter typically comprises a laser diode 60. Preferably the transmitter 14 employs a vertical cavity surface emitting laser or an edge emitting laser coupled to a single or mufti-mode fiber 16.
3o Preferably each fiberoptic receiver 48 comprises a photodiode 62 which converts the optical signal to RF. A 10 KHz detector fi4 detects and filters out a 10 KHz tone.
If the 10 KHz tone is not detected, this is an indication of a break in the communications link and detector 64 causes illumination of a pilot LED 66. Another indication of a break in the WO 98/27748 PCT/a,97/00411 communications link is the absence of received light, which may be indicated by an optical alarm 68.
Reference is now made to Fig. 4 which illustrates a soft limiter 100, constructed and operative in accordance with a preferred embodiment of the present invention. At the uplink, one or more mobile telephones situated very close to the remote antenna may overdrive laser diode 60. Soft limiter 100 may be used at the uplink to prevent laser diode 60 from being overdriven, and thereby prevent non-linear distortion in all of the services distributed. At the downlink, soft limiter 100 protects any of the wireless services from inadvertently increasing input power to base unit 10.
to Soft limiter 100 preferably includes a switched attenuator 102, a comparator 104 and an RF power Level detector 106, as shown in Fig. 4.
Reference is now made to Fig. SA which is a block diagram of part of the circuitry of Fig. 2. There are a number of options of antenna communications with the communications system of the present invention. At the uplink portion of the communications system, jumpers may be used to connect the GSM antenna 28 and the PCS antenna 30 to local and/or remote antennas. Specifically, a jumper 70 may be used to connect GSM
antenna 28 solely to an internal antenna 72. An additional jumper 72 may be used to connect GSM
antenna 28 to a local antenna 76, which is preferably the same internal antenna 72, and to a remote antenna 78. Remote antenna 78 preferably is DC powered to allow for amplification 2o and may be connected by coax. Local antenna 76 and remote antenna 78 are preferably connected via a power divider/combiner 80. The foregoing description applies equally for PCS
antenna 30, as shown in Fig. SA.
The signals from each GSM antenna 28 and PCS antenna 30 are each input to a low noise amplifier (LNA) 82 via an antenna duplexer 84 in order to enable the same antenna to be used for transmission and reception. The signals from both the GSM
antenna 28 and PCS
antenna 30 are combined by combiner 42 and input to fiberoptic transmitter 44.
At the downlink, the optical signal from base unit 10 is amplified and demultiplexed by a demultiplexer 85. Preferably three signals are demultiplexed. A 10 KHz tone is input to transmitter 44, a low frequency paging signal is input to paging loop antenna 26, and an RF signal, comprising combined GSM and PCS signals, is input to a demultiplexer 86. These signals are each input to their respective antenna via antenna duplexer 84.
WO 98/27748 PCT/8.97/00411 As seen in Fig. SA, a gain control is provided at receiver 22 and transmitter 44.
The gain level is controlled by the amplitude of the 10 KHz pilot tone. The simultaneous gain control of the transmitted and received signals deternnines the size of the local cell.
Reference is now made to Fig. 5B which illustrates microprocessor control of remote units 20. Instead of analog control using the 10 KHz tone, a low frequency data signal may be multiplexed by a multiplexer 90 along with the RF signal. A
microprocessor 92 at each remote unit 20 receives the signal. The absence of l:he signal indicates an alarm status which microprocessor 92 relays to a microprocessor (not shown) at base unit 10. The low frequency data signal may be used for status and control of remote unit 20, and may include the following to control parameters:
a. Cell size: This controls gains of the transmitted and received signals b. Balance between transmitted and received signals c. Threshold of soft limiter 100.
Control parameters may be from base unit 10 or remotely controlled through a network management interface. However, it is sometiames more convenient to set these control parameters locally while the unit is tested in situ. Reference is now made to Fig. SC which illustrates a remote control unit 110 for remotely controlling control parameters of a local cell, in accordance with a preferred embodiment of the present invention. Remote control unit 110 preferably includes a plurality of control buttons, such as a cell size control button 112 and a 2o balance control button 114. For example, control button 112 may control volume, while control button 114 may control transmit cell balance, such as stereo balance.
An additional control button 116 may be provided for controlling threshold of soft limiter 100.
Reference is now made to Fig. 6, which is a simplified block diagram illustration of network management apparatus useful in the apparatus of Figs. I - SC. The network management apparatus typically comprises a microprocessor 200 which communicates typically via an RS 232 interface 202 and a modem 204 with an external communications network such as an ordinary telephone network. The microprocessor receives status indications from alarm indicators 206 which indicate malfunctions in remote units 20 (Fig. 1 ) based on receipt of loop back signals therefrom.
3o Microprocessor 200 provides gain conl:ro) signals to the remote units via a D/A
converter 208 and a loop back signal generator :210. Loop back signal generator 210 preferably operates at approximately 10 KHz.
Reference is now made to Fig. 7, which is an illustration of the use of directional antennas in a system of the type illustrated in Figs. 1 - 6. Fig.
7 shows the use of two such antennas, indicated by reference numerals 220 and 222, which are aimed in different directions. Directionality is achieved by rotating the ground plane around the vertical antenna.
Antennas 28 and 30 (Fig. 2) are preferably antennas of this type. This allows for tuning and balancing of cell size once the basic fixed installations have been made. This further allows for future tuning and balancing to overcome obstacles or partitions which may be constructed in the building in the future.
It will be appreciated by persons skilled in the art that the present invention is to not limited by what has been particularly shown and described hereinabove.
Rather the scope of the present invention is defined only by the claims which follow:
7 shows the use of two such antennas, indicated by reference numerals 220 and 222, which are aimed in different directions. Directionality is achieved by rotating the ground plane around the vertical antenna.
Antennas 28 and 30 (Fig. 2) are preferably antennas of this type. This allows for tuning and balancing of cell size once the basic fixed installations have been made. This further allows for future tuning and balancing to overcome obstacles or partitions which may be constructed in the building in the future.
It will be appreciated by persons skilled in the art that the present invention is to not limited by what has been particularly shown and described hereinabove.
Rather the scope of the present invention is defined only by the claims which follow:
Claims
What is claimed is:
1. A wireless communications station comprising:
a base unit comprising:
a communications interface for communicating with plural wireless communications networks;
a received communications. combiner for combining received communications signals received from said plural wireless communications networks into a single radio frequency output;
a transmit communications splitter for splitting previously combined transmit communications signals to be transmitted to said plural wireless communications networks into plural radio frequency outputs;
at least one frberoptic transmitter receiving said single radio frequency output and providing a corresponding optical output; and at least one fiberoptic receiver receiving an optical input and providing an RF output containing previously combined transmit communications signals;
a plurality of remote units, each comprising:
plural antennas for communicating with communicators along plural wireless communications networks;
a received communications splitter for splitting previously combined received communications signals from said base unit and supplying them to said plural antennas;
a transmit communications combiner for combining transmit communications signals from said plural antennas into a combined radio frequency output;
a fiberoptic transmitter receiving said combined radio frequency output and providing a corresponding optical output; and a fiberoptic receiver receiving an optical input and providing an RF
output to said received communications splitter containing previously received transmit communications signals;
a first optical fiber connecting each fiberoptic transmitter of said base unit with a corresponding fiberoptic receiver in a corresponding remote unit; and a second optical fiber connecting each fiberoptic transmitter of a remote unit with a corresponding fiberoptic receiver in said base unit.
2. The wireless communications station according to claim 1 and wherein each remote unit also comprises a diplexer interposed between each of said plural antennas and said combiner and said splitter, so as to enable simultaneous two way communications via each antenna at different frequencies for transmission and reception.
3. A mobile communications system comprising a base unit comprising:
a communications interface for communicating with plural wireless communications networks;
a plurality of antennas each communicating with the communications interface via a fiber network; and a single duplex cable interconnecting each of said plurality of antennas with said communications interface via the fiber network.
4. The system according to claim 3 and wherein the plural wireless communications networks comprise at least two communications networks selected from the group consisting of cellular telephone networks, cordless telephones, wide area data networks, wireless local area networks, personal communications systems, personal communications networks, paging/messaging networks and satellite mobile systems.
5. The wireless communications station according to claim 1 or claim 2 and wherein a low frequency control signal is multiplexed by said communications interface onto said optical fiber for providing loop back alarm status of each remote unit and for providing control signals thereto, which control amplifier gain and balance thereof.
6. The wireless communications station according to claim 1 or claim 2 and wherein a low frequency data signal is multiplexed by said communications interface to a microprocessor for providing loop back alarm status of each remote unit and for providing control signals thereto, which control amplifier gain and balance thereof.
7. The wireless communications station according to claim 1 or claim 2 and wherein said plural antennas comprise at last one swivel mounted directional antenna whose direction may be adjusted on site.
8. The wireless communications station according to claim 1 or claim 2 and wherein said base unit also comprises tuning circuitry which permits dynamic tuning and transmission/reception balance of cell size of each of the remote units.
9. The wireless communications station according to claim 1 or claim 2 and wherein said base unit also comprises a network management interface which allows monitoring of the operational status of a base unit and the remote units connected thereto.
10. The wireless communications station according to claim 1 or claim 2 and wherein said fiberoptic transmitter employs a vertical cavity surface emitting laser coupled to a single or multi mode fiber.
ll. The wireless communications station according to claim 1 or claim 2 and wherein said fiberoptic transmitter employs an edge emitting laser coupled to a single or multi mode fiber.
12. The wireless communications station according to claim 1 or claim 2 and comprising a soft limiter for substantially preventing distortion due to an inadvertent increase in communication power.
13. The system according to claim 3 or claim 4 and wherein a low frequency control signal is multiplexed by said communications interface onto said optical fiber for providing loop back alarm status of each remote unit and for providing control signals thereto, which control amplifier gain and balance thereof.
14. The system according to claim 3 or claim 4 and wherein a low frequency data signal is multiplexed by said communications interface to a microprocessor for providing loop back alarm status of each remote unit and for providing control signals thereto, which control amplifier gain and balance thereof.
15. The system according to claim 3 or claim 4 and wherein said plural antennas comprise at last one swivel mounted directional antenna whose direction may be adjusted on site.
16. The system according to claim 3 or claim 4 and wherein said base unit also comprises tuning circuitry which permits dynamic tuning and transmission/reception balance of cell size of each of the remote units.
17. The system according to claim 3 or claim 4 and wherein said base unit also comprises a network management interface which allows monitoring of the operational status of a base unit and the remote units connected thereto.
18. The system according to claim 3 or claim 4 and wherein said fiberoptic transmitter employs a vertical cavity surface emitting laser coupled to a single or multi mode fiber.
19. The system according to claim 3 or claim 4 and wherein said fiberoptic transmitter employs an edge emitting laser coupled to a single or multi mode fiber.
20. The system according to claim 3 or claim 4 and comprising a soft limiter for substantially preventing distortion due to an inadvertent increase in communication power.
21. A microcellular telecommunications system employing a fiber network comprising optical fibers which may be single or mufti mode and optical transmitters for transmitting signals along the optical fibers, the optical transmitters comprising a vertical cavity surface emitting laser.
22. A microcellular telecommunications system employing a fiber network comprising optical fibers which may be single or mufti mode and optical transmitters for transmitting signals along the optical fibers, the optical transmitters comprising an edge emitting laser.
23. A microcellular telecommunications system according to claim 22 wherein said edge emitting laser comprises a distributed feedback laser integrated with an optical isolator.
1. A wireless communications station comprising:
a base unit comprising:
a communications interface for communicating with plural wireless communications networks;
a received communications. combiner for combining received communications signals received from said plural wireless communications networks into a single radio frequency output;
a transmit communications splitter for splitting previously combined transmit communications signals to be transmitted to said plural wireless communications networks into plural radio frequency outputs;
at least one frberoptic transmitter receiving said single radio frequency output and providing a corresponding optical output; and at least one fiberoptic receiver receiving an optical input and providing an RF output containing previously combined transmit communications signals;
a plurality of remote units, each comprising:
plural antennas for communicating with communicators along plural wireless communications networks;
a received communications splitter for splitting previously combined received communications signals from said base unit and supplying them to said plural antennas;
a transmit communications combiner for combining transmit communications signals from said plural antennas into a combined radio frequency output;
a fiberoptic transmitter receiving said combined radio frequency output and providing a corresponding optical output; and a fiberoptic receiver receiving an optical input and providing an RF
output to said received communications splitter containing previously received transmit communications signals;
a first optical fiber connecting each fiberoptic transmitter of said base unit with a corresponding fiberoptic receiver in a corresponding remote unit; and a second optical fiber connecting each fiberoptic transmitter of a remote unit with a corresponding fiberoptic receiver in said base unit.
2. The wireless communications station according to claim 1 and wherein each remote unit also comprises a diplexer interposed between each of said plural antennas and said combiner and said splitter, so as to enable simultaneous two way communications via each antenna at different frequencies for transmission and reception.
3. A mobile communications system comprising a base unit comprising:
a communications interface for communicating with plural wireless communications networks;
a plurality of antennas each communicating with the communications interface via a fiber network; and a single duplex cable interconnecting each of said plurality of antennas with said communications interface via the fiber network.
4. The system according to claim 3 and wherein the plural wireless communications networks comprise at least two communications networks selected from the group consisting of cellular telephone networks, cordless telephones, wide area data networks, wireless local area networks, personal communications systems, personal communications networks, paging/messaging networks and satellite mobile systems.
5. The wireless communications station according to claim 1 or claim 2 and wherein a low frequency control signal is multiplexed by said communications interface onto said optical fiber for providing loop back alarm status of each remote unit and for providing control signals thereto, which control amplifier gain and balance thereof.
6. The wireless communications station according to claim 1 or claim 2 and wherein a low frequency data signal is multiplexed by said communications interface to a microprocessor for providing loop back alarm status of each remote unit and for providing control signals thereto, which control amplifier gain and balance thereof.
7. The wireless communications station according to claim 1 or claim 2 and wherein said plural antennas comprise at last one swivel mounted directional antenna whose direction may be adjusted on site.
8. The wireless communications station according to claim 1 or claim 2 and wherein said base unit also comprises tuning circuitry which permits dynamic tuning and transmission/reception balance of cell size of each of the remote units.
9. The wireless communications station according to claim 1 or claim 2 and wherein said base unit also comprises a network management interface which allows monitoring of the operational status of a base unit and the remote units connected thereto.
10. The wireless communications station according to claim 1 or claim 2 and wherein said fiberoptic transmitter employs a vertical cavity surface emitting laser coupled to a single or multi mode fiber.
ll. The wireless communications station according to claim 1 or claim 2 and wherein said fiberoptic transmitter employs an edge emitting laser coupled to a single or multi mode fiber.
12. The wireless communications station according to claim 1 or claim 2 and comprising a soft limiter for substantially preventing distortion due to an inadvertent increase in communication power.
13. The system according to claim 3 or claim 4 and wherein a low frequency control signal is multiplexed by said communications interface onto said optical fiber for providing loop back alarm status of each remote unit and for providing control signals thereto, which control amplifier gain and balance thereof.
14. The system according to claim 3 or claim 4 and wherein a low frequency data signal is multiplexed by said communications interface to a microprocessor for providing loop back alarm status of each remote unit and for providing control signals thereto, which control amplifier gain and balance thereof.
15. The system according to claim 3 or claim 4 and wherein said plural antennas comprise at last one swivel mounted directional antenna whose direction may be adjusted on site.
16. The system according to claim 3 or claim 4 and wherein said base unit also comprises tuning circuitry which permits dynamic tuning and transmission/reception balance of cell size of each of the remote units.
17. The system according to claim 3 or claim 4 and wherein said base unit also comprises a network management interface which allows monitoring of the operational status of a base unit and the remote units connected thereto.
18. The system according to claim 3 or claim 4 and wherein said fiberoptic transmitter employs a vertical cavity surface emitting laser coupled to a single or multi mode fiber.
19. The system according to claim 3 or claim 4 and wherein said fiberoptic transmitter employs an edge emitting laser coupled to a single or multi mode fiber.
20. The system according to claim 3 or claim 4 and comprising a soft limiter for substantially preventing distortion due to an inadvertent increase in communication power.
21. A microcellular telecommunications system employing a fiber network comprising optical fibers which may be single or mufti mode and optical transmitters for transmitting signals along the optical fibers, the optical transmitters comprising a vertical cavity surface emitting laser.
22. A microcellular telecommunications system employing a fiber network comprising optical fibers which may be single or mufti mode and optical transmitters for transmitting signals along the optical fibers, the optical transmitters comprising an edge emitting laser.
23. A microcellular telecommunications system according to claim 22 wherein said edge emitting laser comprises a distributed feedback laser integrated with an optical isolator.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IL119832 | 1996-12-15 | ||
| IL11983296A IL119832A (en) | 1996-12-15 | 1996-12-15 | Wireless communications systems employing optical fibers |
| US08/886,695 | 1997-07-01 | ||
| US08/886,695 US5969837A (en) | 1996-12-15 | 1997-07-01 | Communications system |
| PCT/IL1997/000411 WO1998027748A2 (en) | 1996-12-15 | 1997-12-15 | Wireless communications station and system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2275251A1 true CA2275251A1 (en) | 1998-06-25 |
Family
ID=26323334
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002275251A Abandoned CA2275251A1 (en) | 1996-12-15 | 1997-12-15 | Wireless communications station and system |
Country Status (6)
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| EP (1) | EP0950326A4 (en) |
| JP (1) | JP2001506826A (en) |
| AU (1) | AU735820B2 (en) |
| BR (1) | BR9713714A (en) |
| CA (1) | CA2275251A1 (en) |
| WO (1) | WO1998027748A2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6480510B1 (en) | 1998-07-28 | 2002-11-12 | Serconet Ltd. | Local area network of serial intelligent cells |
| GB9923070D0 (en) * | 1999-09-29 | 1999-12-01 | Nokia Telecommunications Oy | Multilayer telecommunications network |
| US6842459B1 (en) | 2000-04-19 | 2005-01-11 | Serconet Ltd. | Network combining wired and non-wired segments |
| US9094226B2 (en) | 2000-08-30 | 2015-07-28 | Broadcom Corporation | Home network system and method |
| AU2001288532A1 (en) | 2000-08-30 | 2002-03-13 | Tiaris, Inc. | A home network system and method |
| US8724485B2 (en) | 2000-08-30 | 2014-05-13 | Broadcom Corporation | Home network system and method |
| IT1403065B1 (en) | 2010-12-01 | 2013-10-04 | Andrew Wireless Systems Gmbh | DISTRIBUTED ANTENNA SYSTEM FOR MIMO SIGNALS. |
| GB0229238D0 (en) * | 2002-12-13 | 2003-01-22 | Univ London | An optical communication system |
| IL154921A (en) | 2003-03-13 | 2011-02-28 | Mosaid Technologies Inc | Telephone system having multiple distinct sources and accessories therefor |
| IL157787A (en) | 2003-09-07 | 2010-12-30 | Mosaid Technologies Inc | Modular outlet for data communications network |
| DE10344278B4 (en) * | 2003-09-24 | 2013-10-31 | Nokia Siemens Networks Gmbh & Co. Kg | Device for a radio station which supports several radio standards |
| IL159838A0 (en) | 2004-01-13 | 2004-06-20 | Yehuda Binder | Information device |
| US7796554B2 (en) | 2004-03-29 | 2010-09-14 | Utstarcom Telecom Co., Ltd. | Method for resource management and method for traffic guidance in the multimode radio network |
| FR2868634A1 (en) * | 2004-04-02 | 2005-10-07 | Evolium Sas Soc Par Actions Si | Data flow transmitting method, involves receiving data flows from radio sources and temporally multiplexing data flows based on selected multiplexing pattern to transmit flows to processing equipment in form of multiplexed frames |
| US7697522B2 (en) | 2006-11-20 | 2010-04-13 | Broadcom Corporation | Systems and methods for aggregation of packets for transmission through a communications network |
| US7782850B2 (en) | 2006-11-20 | 2010-08-24 | Broadcom Corporation | MAC to PHY interface apparatus and methods for transmission of packets through a communications network |
| US8345553B2 (en) | 2007-05-31 | 2013-01-01 | Broadcom Corporation | Apparatus and methods for reduction of transmission delay in a communication network |
| US9112717B2 (en) | 2008-07-31 | 2015-08-18 | Broadcom Corporation | Systems and methods for providing a MoCA power management strategy |
| CN102369678B (en) * | 2009-02-03 | 2015-08-19 | 康宁光缆系统有限责任公司 | Based on the distributing antenna system of optical fiber, assembly and the correlation technique for calibrating distributing antenna system based on optical fiber, assembly |
| US8553547B2 (en) | 2009-03-30 | 2013-10-08 | Broadcom Corporation | Systems and methods for retransmitting packets over a network of communication channels |
| US20100254278A1 (en) | 2009-04-07 | 2010-10-07 | Broadcom Corporation | Assessment in an information network |
| US8867355B2 (en) | 2009-07-14 | 2014-10-21 | Broadcom Corporation | MoCA multicast handling |
| US8942250B2 (en) | 2009-10-07 | 2015-01-27 | Broadcom Corporation | Systems and methods for providing service (“SRV”) node selection |
| US8611327B2 (en) | 2010-02-22 | 2013-12-17 | Broadcom Corporation | Method and apparatus for policing a QoS flow in a MoCA 2.0 network |
| US8514860B2 (en) | 2010-02-23 | 2013-08-20 | Broadcom Corporation | Systems and methods for implementing a high throughput mode for a MoCA device |
| KR102163548B1 (en) | 2010-10-01 | 2020-10-12 | 콤스코프 테크놀로지스, 엘엘씨 | Distributed antenna system for MIMO signals |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5125100A (en) * | 1990-07-02 | 1992-06-23 | Katznelson Ron D | Optimal signal synthesis for distortion cancelling multicarrier systems |
| IL100213A (en) * | 1990-12-07 | 1995-03-30 | Qualcomm Inc | CDMA microcellular telephone system and distributed antenna system therefor |
| US5339184A (en) * | 1992-06-15 | 1994-08-16 | Gte Laboratories Incorporated | Fiber optic antenna remoting for multi-sector cell sites |
| US5627879A (en) * | 1992-09-17 | 1997-05-06 | Adc Telecommunications, Inc. | Cellular communications system with centralized base stations and distributed antenna units |
| DE59308072D1 (en) * | 1992-12-03 | 1998-03-05 | Siemens Ag | Bidirectional optical transmitter and receiver module |
| DE4440976A1 (en) * | 1994-11-17 | 1996-05-23 | Ant Nachrichtentech | Optical transmitter and receiver with a surface emitting laser |
-
1997
- 1997-12-15 JP JP52751698A patent/JP2001506826A/en not_active Ceased
- 1997-12-15 WO PCT/IL1997/000411 patent/WO1998027748A2/en not_active Application Discontinuation
- 1997-12-15 EP EP97947850A patent/EP0950326A4/en not_active Withdrawn
- 1997-12-15 BR BR9713714-6A patent/BR9713714A/en not_active IP Right Cessation
- 1997-12-15 AU AU54082/98A patent/AU735820B2/en not_active Ceased
- 1997-12-15 CA CA002275251A patent/CA2275251A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| BR9713714A (en) | 2000-06-13 |
| JP2001506826A (en) | 2001-05-22 |
| WO1998027748A3 (en) | 1998-09-17 |
| WO1998027748A2 (en) | 1998-06-25 |
| EP0950326A4 (en) | 2002-03-13 |
| AU735820B2 (en) | 2001-07-19 |
| AU5408298A (en) | 1998-07-15 |
| EP0950326A2 (en) | 1999-10-20 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued | ||
| FZDE | Discontinued |
Effective date: 20051215 |