Multi-point to point communication system with remote unit burst identification

• US 6,330,241 B1
• Filed: 09/15/1999
• Issued: 12/11/2001
• Est. Priority Date: 02/06/1995
• Status: Expired due to Term

• Current Assignee: HTC Corporation
• Original Assignee: ADC Telecommunications Incorporated (TE Connectivity Limited)
• Inventors: Fort, Michael J.
• Primary Examiner(s): CUMMING, WILLIAM D
• Application Number:
  US09/396,139
• Time in Patent Office: 818 Days
• Field of Search: 455/3.1, 455/422, 370/395, 709/217
• US Class Current: 370/395.1
• 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 27/26524 : Fast Fourier transform [FFT] or discrete Fourier transform [DFT] demodulators in combination with other circuits for demodulation
• CPC Class Codes: H04L 27/2654 : Filtering per subcarrier, e.g. filterbank multicarrier [FBMC]
• 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 method of burst identification in a communication is described. The method includes receiving, at each of a first set of m service units, a plurality of modulated orthogonal carriers having information modulated thereon in a plurality of bands of a first frequency bandwidth transmitted from a head end terminal, wherein the first band includes at least one control channel. The method further includes scanning, at each of the m service units, the at least one control channel to detect identification information corresponding to each of the m service units to identify a particular band of the plurality of bands that each of the m service units is to use for receiving information from the head end terminal.

Claims

1. A method of 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 n 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 during a first predetermined time period, the identification information for each of the plurality of n remote units being transmitted out of phase with respect to the identification information for the other n remote units; and

scanning, at each of the n 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 n remote units to identify a particular region of the plurality of regions that each of the n remote units is to use for receiving information from the head end.

2. The method according to claim 1 further comprising:

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

serially performing upstream synchronization for the n remote units for communication with the head end during a second predetermined time period after the first predetermined time period.

3. The method according to claim 2, wherein performing upstream synchronization includes synchronizing the n remote units such that when information is modulated on at least one carrier by 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.

4. The method according to claim 3, further comprising repeating the transmitting, scanning, identifying and serially performing synchronization for an additional set of remote units of the plurality of remote units.

5. The method according to claim 4, further comprising resetting a remote unit of the n remote units which failed to accomplish synchronization during the second predetermined time period by a reset period equal to the sum of the first and second predetermined time periods to restart a process to establish communication between the head end and the remote unit.

6. The method according to claim 2, wherein the first and second frequency bandwidths are substantially equivalent but non-interfering.

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

means for 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, the transmitting means further for periodically transmitting identification information corresponding to each remote unit of a set of n remote units of the plurality of remote units on the at least one control channel of one of the plurality of regions of the first frequency bandwidth during a first predetermined time period of an identification and synchronization time period, the identification information for each remote unit of the set of n remote units being transmitted out of phase with respect to the identification information for the other remote units of the set of n remote units;

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

means, at each of the n remote units, for modulating at least upstream telephony information on at least one carrier in a second frequency bandwidth orthogonal at the head end terminal to at least one other carrier in the second frequency bandwidth and for adjusting at least one local transmission characteristic in response to an adjustment command from the head end; and

means at the head end for detecting the at least one local transmission characteristic of each of the n remote units and for generating the adjustment commands as a function of the detected at least one transmission characteristic for transmittal to the n remote units to serially perform synchronization for each of the n remote units during a second predetermined time period of the identification and synchronization time period.

8. A method of burst identification in a communication system, comprising:

receiving, at each of a first set of m service units, a plurality of modulated orthogonal carriers having information modulated thereon in a plurality of bands of a first frequency bandwidth transmitted from a head end terminal, wherein the first band includes at least one control channel; and

scanning, at each of the m service units, the at least one control channel to detect identification information corresponding to each of the m service units to identify a particular band of the plurality of bands that each of the m service units is to use for receiving information from the head end terminal.

9. The method of claim 8, wherein scanning, at each of the m service units, the at least one control channel comprises scanning, at each of the m service units, the at least one control channel to detect identification information corresponding to each of the m service units to identify a particular band of the plurality of bands that each of the m service units is to use for receiving information from the head end terminal wherein the identification information detected for each of the m service units is transmitted out of phase with respect to the identification information of the other m service units.

10. The method of claim 8, further comprising:

identifying a band in a second frequency bandwidth in which each of the m service units is to transmit within; and

serially performing upstream synchronization for the m service units for communication with the head end terminal.

11. The method of claim 10, wherein serially performing synchronization includes synchronizing the m remote units such that when information is modulated on at least one carrier by one of the m service 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.

12. The method of claim 8, further comprising repeating the receiving and scanning for a second set of m service units.

13. The method of claim 8, further comprising repeating the receiving and scanning for another set of service units.

14. The method of claim 11, further comprising repeating the receiving, scanning, identifying and serially performing synchronization for an additional set of service units of the plurality of service units.

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

receiving, at each of the plurality of service units, a plurality of modulated orthogonal carriers having information modulated thereon in 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;

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 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 during a first predetermined time frame; and

wherein the unique identifier for each of the plurality of service units is transmitted out of phase with respect to the unique identifier for the other remote units.

16. The method of claim 15, 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.

17. The method of claim 15, wherein detecting a unique identifier further comprises storing a personal identification number address code transmitted within the unique identifier.

18. The method of claim 15, further comprises enabling upstream transmission at each of the plurality of service units.

19. The method of claim 18, wherein enabling upstream transmission comprises transmitting a synchronization pattern to the head end terminal on a synchronization channel.

20. The method of claim 15, 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.

21. A communication system, comprising:

a head end terminal;

a first plurality of service units;

a distribution network, coupled between the head end terminal and the first plurality of service units;

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 information channels thereon, each of the regions having at least one control channel associated therewith for transmission of control data, wherein the head end multicarrier modem periodically transmits identification information corresponding to each service unit on the at least one control channel during a first predetermined time period of an identification and activation time period; and

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

wherein each of the first plurality of m service units include;

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 the 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 identification information for the service unit to determine within which region of the first frequency bandwidth the service unit is to receive information, wherein the identification information for each service unit is out of phase with respect to the identification information for the other service units of the first plurality of service units.

22. The communication system of claim 21, wherein the identification information includes a personal identification number address for each of the service units.

23. The communication system of claim 21, wherein the identification information is based on the serial number of the second multicarrier modem.

24. A communication system having a distribution network between a head end and a plurality of remote units, comprising:

a head end terminal for 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, the head end terminal further periodically transmitting identification information corresponding to each remote unit of a set of n remote units of the plurality of remote units on the at least one control channel of one of the plurality of regions of the first frequency bandwidth during a first predetermined time period of an identification and synchronization time period, the identification information for each remote unit of the set of n remote units being transmitted out of phase with respect to the identification information for the other remote units of the set of n remote units;

a scanner, associated with each of the n remote units, for scanning the at least one control channel of each of the plurality of regions in the first frequency bandwidth to detect identification information during the first predetermined time period corresponding to each of the n remote units to identify a particular region of the plurality of regions that each of the n remote units is to use for receiving information from the head end;

a multicarrier modem operatively coupled to the distribution network at each of the n remote units for modulating at least upstream telephony information on at least one carrier in a second frequency bandwidth orthogonal at the head end terminal to at least one other carrier in the second frequency bandwidth and for adjusting at least one local transmission characteristic in response to an adjustment command from the head end; and

a head end controller coupled to the multicarrier modem for detecting the at least one local transmission characteristic of each of the n remote units and for generating the adjustment commands as a function of the detected at least one transmission characteristic for transmittal to the n remote units to serially perform synchronization for each of the n remote units during a second predetermined time period of the identification and synchronization time period.

25. A method of initializing a plurality of service units, the method comprising:

transmitting information from a head end to the plurality of service units in a plurality of regions of a first frequency bandwidth, each of the regions having at least one control channel associated therewith;

periodically transmitting identification information corresponding to each service unit of a set of m service units of the plurality of remote units on the at least one control channel of one of the plurality of regions of the first frequency bandwidth during a first predetermined time period of an identification and synchronization time period, the identification information for each remote unit of the set of n remote units being transmitted out of phase with respect to the identification information for the other remote units of the set of n remote units;

scanning, at each of the m service units, the at least one control channel of each of the plurality of regions in the first frequency bandwidth to detect identification information during the first predetermined time period corresponding to each of the m service units to identify a particular region of the plurality of regions that each of the m service units is to use for receiving information from the head end;

modulating, at each of the m service units, at least upstream telephony information on at least one carrier in a second frequency bandwidth orthogonal at the head end terminal to at least one other carrier in the second frequency bandwidth;

adjusting, at each of the m service units, at least one local transmission characteristic in response to an adjustment command from the head end;

detecting, at the head end terminal, the at least one local transmission characteristic of each of the m service units;

generating, at the head end terminal, the adjustment commands as a function of the detected at least one transmission characteristic for transmittal to the m service units; and

serially performing synchronization for each of the m service units during a second predetermined time period of the identification and synchronization time period.