WO2009088681A1 - Systeme de diversite de ligne electrique/rf - Google Patents

Systeme de diversite de ligne electrique/rf Download PDF

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Publication number
WO2009088681A1
WO2009088681A1 PCT/US2008/087226 US2008087226W WO2009088681A1 WO 2009088681 A1 WO2009088681 A1 WO 2009088681A1 US 2008087226 W US2008087226 W US 2008087226W WO 2009088681 A1 WO2009088681 A1 WO 2009088681A1
Authority
WO
WIPO (PCT)
Prior art keywords
channels
control module
digital control
base unit
electronic device
Prior art date
Application number
PCT/US2008/087226
Other languages
English (en)
Inventor
Alan Stettler
Scott Smith
Original Assignee
Phonex Corporation
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 Phonex Corporation filed Critical Phonex Corporation
Publication of WO2009088681A1 publication Critical patent/WO2009088681A1/fr

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/54—Systems for transmission via power distribution lines
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B2203/00—Indexing scheme relating to line transmission systems
    • H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
    • H04B2203/5429—Applications for powerline communications
    • H04B2203/5437—Wired telephone
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B2203/00—Indexing scheme relating to line transmission systems
    • H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
    • H04B2203/5429—Applications for powerline communications
    • H04B2203/5441—Wireless systems or telephone

Definitions

  • the present invention relates to a system and method allowing a first electronic device to transfer data to a second electronic device using an active phone line when the first electronic device is located beyond a physical location of the active phone line.
  • a simplified residential wiring diagram 100 includes only 5 outlets. Each transmission line stub length, in this example, was selected to cause the largest system grief: Stub A and D's length is equal to Vz the wave length of the frequency Fl, Stub B's length is 1 A the wavelength of frequency F2, Stub Cs length is 1 A the wavelength of F2. Stub C and E's length are relatively unimportant as they are terminated at approximately the characteristic impedance of the wiring (120 ohms).
  • the present invention overcomes the limitations of fixed frequency and fixed mode (power line carrier or over-the-air RF) operation.
  • a first electronic device is connected to the extension unit, while a second electronic device is connected to the base unit through an active phone line.
  • the base unit communicates with the extension unit using power lines and/or over-the-air signals using frequency-hopping spread spectrum based on an evaluation of the channels within the power lines and/or the over-the-air signals.
  • the present invention generates diagnostic reports based on the communication status between the base unit, the extension unit, the first electronic device, the second electronic device, and/or the active phone line using caller identification data, frequency-shift keying data, and/or dual-tone multi-frequency signaling data.
  • FIG. 1 is a schematic illustration of a residential wiring diagram
  • FIG. 2 is a schematic illustration of a power line/RF communication system in accordance with an embodiment of the present invention
  • FIG. 3 is a block diagram of a base unit in accordance with an embodiment of the present invention.
  • FIG. 4 is a block diagram of an extension unit in accordance with an embodiment of the present invention.
  • FIG. 5 is an operational flow diagram of an embodiment of the present invention.
  • communication system 200 includes a base unit 208, one or more extension units 202, and one or more telephone devices 201.
  • Base unit 208 is communicatively connected to extension units 202 and to a central office 212.
  • Base unit 208 can be connected to extension units 202 through power lines 204 and/or over-the-air signals 206.
  • the over-the-air signals could be, for example RF signals with over-the-air channels in a 900MHz, or 2.4 GHz band.
  • Power line 204 can be, for example, an AC or DC power line with power line channels in a 2 to 50 MHz band. However, the power line channels and the over-the-air channels could also be found on any number of other bands.
  • base unit 208 can be connected to extension units 202 through an optical connection.
  • base unit 208 is connected to a central office 212 through a telephone cable 210.
  • Base unit 208 can thus provide an interface to communicate with the central office 212 and can receive audio and control signals from central office 212.
  • Base unit 208 also modulates and couples the modulated audio and control signals for transmission across power lines 204 and/or over-the-air signals 206.
  • base unit 208 includes a Data Access Arrangement (DAA)/CODEC module 302, a digital control module 304, a transceiver module 306, an RF/Power line diplexer module 308, an RF interface module 310, a power line driver module 312, and a power line interface module 314.
  • DAA Data Access Arrangement
  • DAA/CODEC module 302 is connected to digital control module 304.
  • DAA/CODEC module 302 includes a DAA and a CODEC and provides an interface for connectivity to telephone networks.
  • the DAA is used to interface with central office 212 (shown in FIG. 2) and provides a proper impedance matching and interfacing.
  • Analog audio is transmitted and received by the DAA and respectively digitized and undigitized by the CODEC.
  • DAA/CODEC module 302 includes one or more interfaces to allow base unit 208 and/or communication system 200 to be compatible with any service that provides telephony functionality such as cellular, cable, fiber optic, VoIP, etc.
  • Digital control module 304 is connected to DAA/CODEC module 302 and transceiver 306.
  • Digital control module 304 manages a flow of the audio data to and from transceiver module 306 and the CODEC.
  • the DAA, CODEC, and RF/power line transceiver modes are managed and controlled by digital control module 304.
  • digital control module 304 uses a frequency evaluation algorithm to determine whether base unit 208 communicates with extension unit 202 in a first operational mode or a second operational mode. In the first operational mode, base unit 208 communicates with extension unit 202 using power line 204 while in the second operation mode, base unit 208 communicates with extension unit 202 using over-the-air signals 206.
  • Digital control module 304 can also enable the selected mode.
  • Transceiver 306 is connected to RF/power line diplexer 308.
  • transceiver 306 is a low cost frequency-hopping, spread-spectrum transceiver such as an Industrial-Scientific-Medical (ISM) transceiver. It is contemplated that transceiver 306 can function as both a transceiver and an RF interface.
  • RF/power line diplexer 308 is connected to transceiver 306, RF interface 310, and powerline driver 312.
  • Rf/power line diplexer 308 includes, for example, filters, switches, an RF mixer, and/or any combination of the above components.
  • a RF mixer (not shown) is used as part of RF/power line diplexer module 308 to "down-mix” the transmitter and “up-mix” the received signal to operate in the range of transceiver 306.
  • RF interface 310 is connected to RF/Powerline diplexer 308 and provides an interface for base unit 208 to communicatively connect with extension units 202 or other devices through over-the-air signals.
  • Powerline driver 312 is connected to RF/Powerline diplexer 308 and powerline interface module 314.
  • Powerline interface module 314 is connected to powerline driver 312 and can include a powerline interface and a switching power supply.
  • Powerline driver 312, as shown in FIG. 3, can provide an interface for base unit 208 to communicatively connect with extension units 202 or other devices through power lines 204 (each shown in FIG. 2).
  • one or more extension units 202 are communicatively connected to base unit 208 and one or more telephone devices 201.
  • extension unit 202 converts a telephone signal received from telephone 201 to a modulated power line compatible signal and couples the converted signal onto AC power line 204.
  • the connection between extension unit 202 and power lines 204 can be made through a wall plug and/or socket.
  • Extension units 202 can receive audio and/or control signals from base unit 208 and decouple and demodulate the audio and/or control signals.
  • extension unit 202 includes a Subscriber Line Interface Circuit (SLIC)/CODEC module 402, a digital control module 404, a transceiver module 406, an RF/Power line diplexer module 408, an RF interface module 410, a power line driver module 412 and a power line interface module 414.
  • SLIC/CODEC module 402 is connected to digital control module 404.
  • SLIC/CODEC module 402 can include a SLIC and an audio CODEC and can emulate connectivity to telephone networks.
  • the SLIC can power telephones 201 in a manner similar to the telephone company and is used to interface to a standard telephony device and provides the proper impedance matching and interfacing.
  • the SLIC is coupled to the audio CODEC and the SLIC audio signals are transferred to digital control module 404.
  • analog audio is transmitted and received by the SLIC and respectively digitized and undigitized by the CODEC.
  • Digital control module 404 is connected to SLIC/CODEC module 402 and transceiver 406.
  • Digital control module 404 manages the flow of the audio data to and from transceiver module 406 and CODEC. Furthermore, digital control module 404 can manage and control the SLIC, the CODEC, and the RF/power line transceiver modes.
  • digital control module 404 instead of digital control module 304 or in conjunction with digital control module 304 can use a frequency evaluation algorithm to determine whether base unit 208 and extension unit 202 communicate in a first operational mode or a second operational mode.
  • Transceiver 406 is connected to digital control module 404 and RF/powerline diplexer 408.
  • transceiver 406 is a low cost frequency-hopping, spread- spectrum transceiver such as Industrial-Scientific-Medical (ISM) transceiver. It is contemplated that transceiver 406 can function as both a transceiver and an RF interface.
  • ISM Industrial-Scientific-Medical
  • RF/power line diplexer 408 is connected to RF interface 410, transceiver 406, and powerline driver 412.
  • RF/power line diplexer 408 may include filters, switches, a RF mixer, and/or any combination of the above components.
  • a RF mixer (not shown) is used as part of RF/power line diplexer module 408 to "down-mix" the transmitter and "up-mix” the received signal to operate in the range of transceiver 406.
  • RF interface 410 is connected to RF/powerline diplexer 408 and can provide an interface for extension units 202 to communicatively connect with base unit 208 or other electronic devices through over-the-air signals.
  • RF interface 410 from extension unit 202 can be communicatively connected to RF interface 310 from base unit 208 allowing extension unit 202 to communicate with base unit 208.
  • Powerline driver 412 is connected to RF/powerline diplexer 408 and power line interface module 414.
  • Powerline interface module 414 is connected to powerline driver 412 and can include a powerline interface and a switching power supply.
  • Powerline driver 412 shown in FIG. 4, can provide an interface for extension unit 202 to communicatively connect with base unit 208 or other devices through power lines 204 (each shown in FIG. 2).
  • powerline driver 412 can be communicatively connected to powerline driver 312 to allowing extension unit 202 and base unit 208 to communicate with each other.
  • one or more telephone devices 201 are connected to extension units 202.
  • Telephone devices 201 can be, for example, any type of electronic device that utilizes a phone line such as telephony devices, a cable set top box, a modem, postage metering return path, credit card readers, etc.
  • at least one telephone device 201 is connected to each extension unit 202.
  • only some extension units 202 have a telephone device 201 connected to them.
  • Central office 212 is connected to base unit 208 and can provide phone connectivity to communication system 200 through telephone cable 210.
  • the connection between central office 212 and base unit 208 can be an over-the air signal and/or an optical connection.
  • the over-the-air signal can be an RF signal, a Bluetooth signal, a wireless Internet signal, etc.
  • Central office 212 can be, for example, a telephone central office while telephone cable 210 can be, for example, an active phone line allowing phone connectivity and a dial tone between communication system 200 and telephone central office 212.
  • telephone central office 212 can include a standard telephone network or the equivalent, a VoIP adapter, a cable interface, a cellular phone, and/or other wireless networks, such as 802.11 and other broadband interfaces.
  • FIG. 5 discloses communication system 200 in operation and extending telephone connectivity, such as allowing access to an active phone line, to remote locations in a residence or small office.
  • base unit 208 is connected to an active phone line such as telephone line 210 and a first electronic device such as telephone device 201 is connected to extension unit 202.
  • Step S504 data is transmitted from telephone device 201 to extension unit 202.
  • base unit 208 analyzes the interference levels of power line channels from power line 204 and over-the-air channels from over-the-air signals 206.
  • the interference level is based on the attenuation found on each channel, and the frequency and level of interfering signals.
  • digital control module 304 in base unit 208 analyzes the interference levels of power line channels from power line 204 and over-the-air channels from over-the-air signals 206.
  • Step S508 base unit 208 and extension unit 202 are configured to communicate with each other based on the analysis of the interference levels of the power line channels and over-the-air channels.
  • the base unit 208 and extension unit 202 are configured to communicate with each other in a first operational mode.
  • base unit 208 communicates with extension unit 202 through the power line channels in power line 204.
  • base unit 208 and extension unit 202 are configured to communicate with each other in a second operational mode.
  • base unit 208 communicates with extension unit 202 through over-the-air channels in over-the-air signals 206.
  • Step S510 base unit 208 dynamically selects one or more channels from the power line channels or the over-the-air channels to use to communicate with extension unit
  • base unit 208 and extension unit 202 communicate in the first operational mode, base unit 208 can analyze the channels in the power line channels and dynamically select a channel to transmit data in the form of a frequency hopping spread spectrum signal to extension unit 202.
  • base unit 208 and extension unit 202 communicate in the second operation mode, base unit 208 can analyze the channels in the over-the-air channels and dynamically select a channel to transmit data in the form of a frequency hopping spread spectrum signal to extension unit 202.
  • base unit 208 can communicate with extension unit 202 using more than one channel at a time.
  • base unit 208 can communicate with extension unit 202 using, for example, two channels at a time.
  • an interference signature of communication system 200 can be reduced. Since the transmit signals are spread over a wider bandwidth than required to transfer the required data rate. This can lower the apparent transmit signal level on each hop frequency, thus lowering the interference level.
  • the fact that the hop frequencies may be selected allows for choosing the individual hop frequencies to match the best frequencies found in the ongoing channel evaluation. Programmable hop frequencies also facilitate co-operation with other nearby systems of the same type by allowing channel sharing.
  • communication system 200 can "be aware” of "like" systems in the region and adjust hop channels accordingly. By monitoring for other systems, systems may co-exist and cooperate among themselves. This can be accomplished by using either different hop frequencies, or by varying the sequence of hop frequencies. This would allow the "reuse" of a particular hop frequency because as long as each system does not try to operate on the same frequencies, in the same time segment, the systems will not interfere with one another.
  • base unit 208 can transmit data to extension unit 202 using other types of communication and modulation techniques such as: Direct Spread, orthogonal frequency-division multiplexing ("OFDM”), single-tone narrow band carrier, frequency modulation (“FM”), frequency-shift keying (“FSK”), phase-shift keying (“PSK”), and/or quadrature amplitude modulation (“QAM”).
  • OFDM orthogonal frequency-division multiplexing
  • FM frequency modulation
  • FSK frequency-shift keying
  • PSK phase-shift keying
  • QAM quadrature amplitude modulation
  • the RF and power line frequency spectrum may be broken into small segments rather than tones to allow for broadband type communication schemes to be used in a similar manner to the described frequency hopping.
  • Step S514 base unit 208 transmits data to a second electronic device such as central office 212.
  • Central office 212 can then transmit the data to another electronic device such as a cable station, a telephone, or other devices which telephone device 201 wishes to communicate to.
  • another electronic device such as a cable station, a telephone, or other devices which telephone device 201 wishes to communicate to.
  • the present invention allows telephone device 201 to communicate with central office 212 as if telephone device 201 was connected directly to telephone cable 210.
  • communication system 200 sets its transmission power level based on an analysis of the conditions of the selected channel to reduce interference with other devices or radio services sharing the same RF spectrum.
  • communication system 200 adapts to the lowest possible transmit power that provides an acceptable level of clarity for communication.
  • the acceptable level of clarity can be based on a predetermined interference level or the like.
  • the continuous monitoring of channel conditions allows base unit 208 and extension unit 202 to continually adapt to changes in the RF characteristics of either the AC wiring system or over-the-air RF by raising/lowering transmit power levels or changing transmit/receive frequencies. This can reduce degradation in communication quality between base unit 208 and extension unit 202.
  • communication system 200 can be used for applications requiring a highly reliable communication channel, such as the transmission of audio, command and control data, remote monitoring, machine to machine communications, and appliance remote diagnostics.
  • communication system 200 may also be used for various applications requiring low to medium data bandwidths such as home control, audio streaming, video, commercial data links, VoIP distribution, data bridging applications and the like.
  • communication system 200 can formulate a diagnostic reports based on the transmission and reception of diagnostic data by base unit 208 or extension unit 202.
  • the diagnostic report can include information regarding a communication status between base unit 208 and a first electronic device such as telephone device 201, base unit 208 and a second electronic device such as central office 212, extension unit 202 and the first electronic device, extension unit 202 and the second electronic device, or an accessibility of the active phone line.
  • communication system 200 can transmit and receive diagnostic data between base unit 208 and the first electronic device, base unit 208 and the second electronic device, extension unit 202 and the first electronic device, or extension unit 202 and the second electronic device as caller identification data, frequency- shift keying data, or dual-tone multi-frequency signaling data.
  • the present invention can also transmit the diagnostic data in a single data message format or a multiple data message format using Bell modulation and/or Telecommunication Standardization Sector ("ITU-T”) v.23 format.
  • ITU-T Bell modulation and/or Telecommunication Standardization Sector
  • Communication system 200 may also include the ability to use caller identification data, frequency-shift keying data, or dual-tone multi-frequency signaling data to communicate with host systems that call into communication system 200 in response to user requests to help in system debugging, troubleshooting and diagnostics reporting. This ability may also be used for sending command and control signals within or without communication system 200, for extensions to peripherals, for extensions to extensions, and for extensions to a remote site communications.
  • communication system 200 could be embedded into cost sensitive devices, reducing a need for a modem to be implemented within the devices. Furthermore manufacturing costs of the cost sensitive device can also be reduced where a single power supply may be shared between communication system 200 and the communication device it is embedded within.
  • the present invention can utilize multiple active phone lines and allow multiple telephone devices 201 to be used at the same time. This can be accomplished using sufficiently high data rate, and co-operating systems.
  • communication system 200 could also utilize a compact embedded antenna on a PC board or an external antenna in base unit 208 and/or extension unit 202. This could improve a performance of communication system 200.
  • multiple color light emitting diodes may be used to provide indications to users of the states of communication system 200 in an easy to decipher "State" or "Error” code. The inclusion of the LEDs also provides an indication of the meaning of a button press.
  • a button press may mean, "Add this extension to the system," in another condition it may mean “Use RF or PLC communications mode.”
  • a high-speed modem may be installed in base unit 208 to transfer the data to special extension units 202 designed to interface directly to digital equipment such as multimedia controllers, computers, and the like.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)

Abstract

L'invention concerne un système et un procédé permettant à un premier dispositif électronique de transférer des données à un deuxième dispositif électronique au moyen d'une ligne téléphonique active lorsque le premier dispositif électronique est situé au-delà de l'emplacement physique de la ligne téléphonique active. Dans un mode de réalisation de la présente invention, un premier dispositif électronique est connecté à une unité d'extension, alors qu'un deuxième dispositif électronique est connecté à l'unité de base par l'intermédiaire d'une ligne téléphonique active. L'unité de base communique avec l'unité d'extension au moyen de lignes électriques et/ou de signaux par voie hertzienne au moyen d'une modulation à spectre étalé à sauts de fréquence basée sur une évaluation des canaux dans les lignes électriques et/ou des signaux par voie hertzienne.
PCT/US2008/087226 2008-01-04 2008-12-17 Systeme de diversite de ligne electrique/rf WO2009088681A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US1915108P 2008-01-04 2008-01-04
US61/019,151 2008-01-04

Publications (1)

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WO2009088681A1 true WO2009088681A1 (fr) 2009-07-16

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PCT/US2008/087226 WO2009088681A1 (fr) 2008-01-04 2008-12-17 Systeme de diversite de ligne electrique/rf

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2017502626A (ja) * 2014-03-06 2017-01-19 ミツビシ・エレクトリック・アールアンドディー・センター・ヨーロッパ・ビーヴィＭｉｔｓｕｂｉｓｈｉ Ｅｌｅｃｔｒｉｃ Ｒ＆Ｄ Ｃｅｎｔｒｅ Ｅｕｒｏｐｅ Ｂ．Ｖ． 無線通信ネットワークの時間および周波数リソースの中から時間および周波数リソースを決定する方法およびデバイス

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US6107912A (en) * 1997-12-08 2000-08-22 Phonex Corporation Wireless modem jack
US20040037311A1 (en) * 2002-08-07 2004-02-26 Phonex Broadband Corporation Digital narrow band power line communication system
US20050267605A1 (en) * 2004-01-07 2005-12-01 Lee Paul K Home entertainment, security, surveillance, and automation control system
US20060077047A1 (en) * 2000-08-14 2006-04-13 Main.Net Communication Ltd. Power line communication system
US20070141990A1 (en) * 2005-12-21 2007-06-21 Zeng Huaiyu Hanks Method and system for adaptive multi rate (AMR) and measurements downlink adaptation

Patent Citations (5)

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Publication number Priority date Publication date Assignee Title
US6107912A (en) * 1997-12-08 2000-08-22 Phonex Corporation Wireless modem jack
US20060077047A1 (en) * 2000-08-14 2006-04-13 Main.Net Communication Ltd. Power line communication system
US20040037311A1 (en) * 2002-08-07 2004-02-26 Phonex Broadband Corporation Digital narrow band power line communication system
US20050267605A1 (en) * 2004-01-07 2005-12-01 Lee Paul K Home entertainment, security, surveillance, and automation control system
US20070141990A1 (en) * 2005-12-21 2007-06-21 Zeng Huaiyu Hanks Method and system for adaptive multi rate (AMR) and measurements downlink adaptation

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2017502626A (ja) * 2014-03-06 2017-01-19 ミツビシ・エレクトリック・アールアンドディー・センター・ヨーロッパ・ビーヴィＭｉｔｓｕｂｉｓｈｉ Ｅｌｅｃｔｒｉｃ Ｒ＆Ｄ Ｃｅｎｔｒｅ Ｅｕｒｏｐｅ Ｂ．Ｖ． 無線通信ネットワークの時間および周波数リソースの中から時間および周波数リソースを決定する方法およびデバイス
US9900129B2 (en) 2014-03-06 2018-02-20 Mitsubishi Electric Corporation Method and device for determining time and frequency resources from amongst time and frequency resources of wireless communications network
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