Communication system transmitting modulated orthogonal carries with service units that scan spectrum to identify assigned band

• US 6,477,354 B1
• Filed: 09/15/1999
• Issued: 11/05/2002
• Est. Priority Date: 02/06/1995
• Status: Expired due to Term

• Current Assignee: HTC Corporation
• Original Assignee: ADC Telecommunications Incorporated (TE Connectivity Limited)
• Inventors: Roberts, Harold A., Brede, Jeffrey, Wadman, Mark S., Kirscht, Robert J., Herrmann, James J., Fort, Michael J.
• Primary Examiner(s): CUMMING, WILLIAM D
• Application Number:
  US09/396,649
• Time in Patent Office: 1,147 Days
• Field of Search: 455/5.1, 370/342, 370/479, 379/474
• US Class Current: 455/7
• CPC Class Codes: G06F 17/14 Fourier, Walsh or analogous domain transformations , e.g. Laplace, Hilbert, Karhunen-Loeve, transforms for correlation function computation G06F17/156; spectrum analysers G01R23/16
• CPC Class Codes: G06F 17/142 Fast Fourier transforms, e.g. using a Cooley-Tukey type algorithm
• CPC Class Codes: H03M 13/1515 Reed-Solomon codes
• CPC Class Codes: H03M 13/356 Unequal error protection [UEP]
• CPC Class Codes: H04B 10/272 Star-type networks or tree-type networks
• CPC Class Codes: H04H 20/69 Optical systems
• CPC Class Codes: H04H 20/77 using carrier waves
• CPC Class Codes: H04H 20/78 CATV [Community Antenna Television] systems
• CPC Class Codes: H04H 20/79 using downlink of the CATV systems, e.g. audio broadcast via CATV network
• CPC Class Codes: H04H 20/80 having frequencies in two or more frequency bands, e.g. medium wave and VHF
• CPC Class Codes: H04H 60/11 Arrangements for counter-measures when a portion of broadcast information is unavailable
• CPC Class Codes: H04H 60/86 accessed over CATV networks
• CPC Class Codes: H04H 60/96 CATV systems for accessing the Internet H04H60/86
• CPC Class Codes: H04H 60/97 using uplink of the CATV systems
• CPC Class Codes: H04J 14/0298 with sub-carrier multiplexing [SCM]
• CPC Class Codes: H04J 3/14 Monitoring arrangements for SDH/SONET rings H04J3/085
• CPC Class Codes: H04K 1/00 Secret communication
• CPC Class Codes: H04K 3/226 Selection of non-jammed channel for communication spectrum sharing arrangements H04W16/14; selection of wireless resources by user or terminal H04W72/02
• CPC Class Codes: H04K 3/255 based on redundancy of transmitted data, transmission path or transmitting source
• CPC Class Codes: H04L 1/004 by using forward error control H04L1/0618 takes precedence; coding, decoding or code conversion, for error detection or correction H03M13/00
• CPC Class Codes: H04L 1/0045 : Arrangements at the receiver end
• CPC Class Codes: H04L 1/0057 : Block codes H04L1/0061, H04L1/0064 take precedence
• CPC Class Codes: H04L 1/0071 : Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/24 : Testing correct operation
• CPC Class Codes: H04L 12/10 : Current supply arrangements
• CPC Class Codes: H04L 12/12 : Arrangements for remote connection or disconnection of substations or of equipment thereof
• CPC Class Codes: H04L 12/2801 : Broadband local area networks
• CPC Class Codes: H04L 12/44 : Star or tree networks
• CPC Class Codes: H04L 2001/0093 : Point-to-multipoint
• CPC Class Codes: H04L 2027/0036 : using a recovered symbol clock
• CPC Class Codes: H04L 2027/0057 : quadrature phase
• CPC Class Codes: H04L 2027/0067 : Phase error detectors
• CPC Class Codes: H04L 25/03866 : using scrambling
• CPC Class Codes: H04L 27/2601 : Multicarrier modulation systems
• CPC Class Codes: H04L 27/2614 : Peak power aspects
• CPC Class Codes: H04L 27/2631 : with polyphase implementation
• CPC Class Codes: H04L 27/2634 : Inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators in combination with other circuits for modulation
• CPC Class Codes: H04L 27/2647 : Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 27/2652 : with polyphase implementation
• CPC Class Codes: H04L 27/2655 : Synchronisation arrangements
• CPC Class Codes: H04L 27/2657 : Carrier synchronisation
• CPC Class Codes: H04L 27/2662 : Symbol synchronisation
• CPC Class Codes: H04L 27/34 : Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
• CPC Class Codes: H04L 41/0213 : Standardised network management protocols, e.g. simple network management protocol [SNMP]
• CPC Class Codes: H04L 41/064 : involving time analysis
• CPC Class Codes: H04L 41/0896 : Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities flow or congestion control using dynamic resource allocation, e.g. in-call renegotiation, H04L47/76
• CPC Class Codes: H04L 43/00 : Arrangements for monitoring or testing data switching networks
• CPC Class Codes: H04L 43/022 : by sampling
• CPC Class Codes: H04L 43/067 : using time frame reporting
• CPC Class Codes: H04L 43/0811 : by checking connectivity
• CPC Class Codes: H04L 43/0817 : by checking functioning
• CPC Class Codes: H04L 43/0823 : Errors, e.g. transmission errors
• CPC Class Codes: H04L 43/0829 : Packet loss
• CPC Class Codes: H04L 43/0847 : Transmission error
• CPC Class Codes: H04L 43/0852 : Delays
• CPC Class Codes: H04L 43/0858 : One way delays
• CPC Class Codes: H04L 43/0864 : Round trip delays
• CPC Class Codes: H04L 43/0882 : Utilisation of link capacity
• CPC Class Codes: H04L 43/16 : Threshold monitoring
• CPC Class Codes: H04L 5/0007 : the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0037 : Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0044 : allocation of payload
• CPC Class Codes: H04L 5/023 : Multiplexing of multicarrier modulation signals multicarrier modulation H04L27/2601
• CPC Class Codes: H04L 5/14 : Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04L 5/143 : for modulated signals H04L5/1469 takes precedence
• CPC Class Codes: H04L 5/1484 : operating bytewise
• CPC Class Codes: H04M 7/006 : Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP) , including next generation networks with a packet-switched transport layer H04L65/00 takes precedence; aspects not specific to the type of network H04M3/00; special services in those networks H04M3/42
• CPC Class Codes: H04M 9/027 : Frequency division multiplex systems
• CPC Class Codes: H04N 21/2221 : being a cable television head-end CATV in broadcast systems H04H20/78
• CPC Class Codes: H04N 21/2383 : Channel coding or modulation of digital bit-stream, e.g. QPSK modulation arrangements for detecting or preventing errors in the information received by adapting the channel coding H04L1/0009; analogue front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 21/2385 : Channel allocation H04N21/266 takes precedence; Bandwidth allocation H04N21/24 takes precedence ; allocation of channels according to the instantaneous demands of the users in time-division multiplex systems H04J3/1682; admission control, resource allocation in open networks H04L12/5692; arrangements for maintenance or administration in data switching networks involving bandwidth and capacity management H04L41/0896; negotiating bandwidth in wireless networks H04W28/16
• CPC Class Codes: H04N 21/2402 : Monitoring of the downstream path of the transmission network, e.g. bandwidth available traffic monitoring in data switching networks H04L43/00; monitoring data switching networks utilization H04L43/0876
• CPC Class Codes: H04N 21/4382 : Demodulation or channel decoding, e.g. QPSK demodulation analog front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 21/6118 : involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/6137 : involving transmission via a telephone network, e.g. POTS
• CPC Class Codes: H04N 21/6168 : involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 7/17309 : Transmission or handling of upstream communications
• CPC Class Codes: H04N 7/22 : Adaptations for optical transmission
• CPC Class Codes: H04W 24/00 : Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 24/08 : Testing, supervising or monitoring using real traffic
• CPC Class Codes: Y02D 30/50 : in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A scanning method for establishing communication between a head end and a plurality of remote units in a multi-point to point communication system is described. The method includes transmitting information from the head end to the plurality of remote units in a plurality of regions of a first frequency bandwidth, each of the regions having at least one control channel associated therewith, identification information corresponding to each of the remote units of the plurality of remote units being periodically transmitted from the head end on the at least one control channel of one of the plurality of regions of the first frequency bandwidth. The method further includes scanning, at each of the remote units, the at least one control channel of each of the plurality of regions in the first frequency bandwidth to detect identification information corresponding to each of the remote units to identify a particular region of the plurality of regions that each of the remote units is to use for receiving information from the head end.

Claims

1. A multi-point to point communication system, comprising:

a distribution network between a head end terminal and a plurality of remote units, the head end terminal for downstream transmission of downstream control data and downstream telephony information in a first frequency bandwidth over the distribution network and for receipt of upstream telephony information and upstream control data in a second frequency bandwidth over the distribution network, the head end terminal including;

head end multicarrier modem means for modulating at least downstream telephony information on a plurality of orthogonal carriers in a plurality of regions of the first frequency bandwidth and for demodulating at least upstream telephony information modulated on a plurality of orthogonal carriers of a plurality of regions in the second frequency bandwidth, the plurality of orthogonal carriers in each of the regions including a plurality of telephony information channels for transmission of telephony information thereon, each of the regions having at least one control channel associated therewith for transmission of control data; and

head end controller means operatively connected to the head end multicarrier modem means for controlling transmission of the downstream telephony information and downstream control data-and for controlling receipt of the upstream control data and upstream telephony information; and

a plurality of service unit modem means, each service unit modem means associated with at least one remote unit and operatively connected to the distribution network for upstream transmission of upstream telephony information and upstream control data in one of the plurality of regions of the second frequency bandwidth and for receipt of the downstream control data and downstream telephony information in one of the plurality of regions in the first frequency bandwidth, each service unit modem means including;

means for scanning each of the plurality of regions in the first frequency bandwidth and for locking onto the at least one control channel in each of the plurality of regions to detect a unique identifier for each service unit modem means to determine which region of the first frequency bandwidth the service unit modem means is to receive information from the head end terminal within.

2. A multi-point to point communication system having a distribution network between a head end a plurality of remote units, comprising:

means for transmitting from the head end a plurality of modulated orthogonal carriers having telephony information modulated thereon in a plurality of regions of a first frequency bandwidth, each of the regions having at least one control channel associated therewith having control information modulated thereon; and

means, at each remote unit, for scanning each of the plurality of regions in the first frequency bandwidth and for locking onto the at least one control channel associated with each of the plurality of regions to detect a unique identifier to determine which region of the first frequency bandwidth the remote unit is to receive information from the head end within.

3. A scanning method for establishing communication between a head end and a plurality of remote units in a multi-point to point communication system, comprising:

transmitting information from the head end to the plurality of remote units in a plurality of regions of a first frequency bandwidth, each of the regions having at least one control channel associated therewith, identification information corresponding to each of the remote units of the plurality of remote units being periodically transmitted from the head end on the at least one control channel of one of the plurality of regions of the first frequency bandwidth; and

scanning, at each of the remote units, the at least one control channel of each of the plurality of regions in the first frequency bandwidth to detect identification information corresponding to each of the remote units to identify a particular region of the plurality of regions that each of the remote units is to use for receiving information from the head end.

4. The method according to claim 3, further including:

identifying a region in a second frequency bandwidth in which the one of the remote units is to transmit within; and

performing synchronization for the one of the remote units such that when information is modulated on at least one carrier by the one of the remote units in the second frequency bandwidth, the at least one carrier is orthogonal at the head end to at least one other carrier in the second frequency bandwidth.

5. A method of initializing and activating a plurality of service units in a distribution network, the method comprising:

receiving, at the plurality of service units, a plurality of modulated orthogonal carriers having a plurality of regions of a first frequency bandwidth transmitted from a head end terminal, each of the regions having at least one control channel associated therewith; and

determining, at each of the plurality of service units, within which region of the first frequency bandwidth the service unit is to receive information, wherein determining includes;

scanning each of the plurality of regions of the first frequency bandwidth; and

detecting a unique identifier corresponding to the service unit.

6. The method of claim 5, wherein scanning each of the plurality of regions of the first frequency bandwidth comprises scanning the at least one control channel of the plurality of regions of the first frequency bandwidth.

7. The method of claim 5, wherein detecting a unique identifier corresponding to the service unit comprises detecting a unique identifier based on a serial number of the service unit.

8. The method of claim 5, wherein detecting a unique identifier further comprises storing a personal identification number address code transmitted with the unique identifier.

9. The method of claim 5, further comprising enabling upstream transmission at each of the plurality of service units.

10. The method of claim 9, wherein enabling upstream transmission comprises transmitting a synchronization pattern to the head end terminal on a synchronization channel.

11. The method of claim 5, further comprising:

identifying a region in a second frequency bandwidth in which the service unit is to transmit within; and

performing synchronization for the service unit such that when information is modulated by the service unit on at least one carrier in the second frequency bandwidth, the at least one carrier is orthogonal at the head end to at least one other carrier in the second frequency bandwidth.

12. A communication system, comprising:

a head end terminal;

at least one service unit;

a distribution network, coupled between the head end terminal and the at least one service unit;

wherein the head end terminal includes;

a head end multicarrier modem adapted to modulate signals on a plurality of orthogonal carriers in a plurality of regions in a first frequency bandwidth, the plurality of orthogonal carriers in each of the regions including a plurality of telephony information channels for transmission of telephony information thereon, each of the regions having at least one control channel associated therewith for transmission of control data; and

a head end controller operatively connected to the head end multicarrier modem for controlling receipt of signals; and

wherein the at least one service unit includes;

a second multicarrier modem, operatively connected to the distribution network for modulating signals on at least one carrier orthogonal at the head end terminal to at least one other carrier in a second frequency bandwidth;

a second controller operatively connected to the second multicarrier modem for controlling the modulation performed by the second multicarrier modem; and

a scanner adapted to scan each of the plurality of regions in the first frequency bandwidth and to lock onto the at least one control channel in each of the plurality of regions and detect a unique identifier for the at least one service unit to determine within which region of the first frequency bandwidth the service unit is to receive information.

13. The system of claim 12, wherein the unique identifier is based on the serial number of the second multicarrier modem.

14. The method of claim 12, wherein the scanner is further adapted to detect a personal identification number address code transmitted with the unique identifier.

15. A communication system, comprising:

a head end terminal adapted to modulate signals on a plurality of orthogonal carriers in a plurality of regions in a first frequency bandwidth, the plurality of orthogonal carriers in each of the regions including a plurality of telephony information channels for transmission of telephony information thereon, each of the regions having at least one control channel associated therewith for transmission of control data;

at least one service unit;

a distribution network, coupled between the head end terminal and the at least one service unit; and

wherein the at least one service unit includes a scanner adapted to scan each of the plurality of regions in the first frequency bandwidth and detect a unique identifier for the at least one service unit to determine within which region of the first frequency bandwidth the service unit is to receive information.

16. The system of claim 15, wherein the unique identifier is based on the serial number of the service unit multicarrier modem.

17. The method of claim 15, wherein the scanner is further adapted to detect a personal identification number address code transmitted with the unique identifier.

18. A method of initializing and activating a plurality of service units in a distribution network, the method comprising:

transmitting from a head end terminal a plurality of modulated orthogonal carriers having a plurality of bands of a first frequency bandwidth, each of the bands having at least one control channel associated therewith and having control information modulated thereon;

receiving, at the plurality of service units, the plurality of modulated orthogonal carriers;

scanning, at each service unit, the at least one control channel to detect identification information; and

identifying, at each service unit, a particular band of the plurality of bands that the service unit is assigned to use for receiving information from the head end terminal.

19. The method of claim 18, wherein scanning the at least one control channel to detect identification information comprises scanning the at least one control channel to detect a unique identifier based on the serial number of the service unit.

20. The method of claim 18, further comprising identifying a band in a second frequency bandwidth within which the service unit is to transmit information.

21. The method of claim 20, further comprising performing synchronization for the service unit such that when information is modulated on at least one carrier by the service unit in the second frequency bandwidth, the at least one carrier is orthogonal at the head end terminal to at least one other carrier in the second frequency bandwidth.

22. The method of claim 20, further comprising serially performing upstream synchronization for the plurality of service units for communication with the head end during a predetermined time period.