Transport of payload information and control messages on multiple orthogonal carriers spread throughout substantially all of a frequency bandwith

• US 6,275,990 B1
• Filed: 09/15/1999
• Issued: 08/14/2001
• Est. Priority Date: 02/06/1995
• Status: Expired due to Term

• Current Assignee: HTC Corporation
• Original Assignee: ADC Telecommunications Incorporated (TE Connectivity Limited)
• Inventors: Dapper, Mark J., Geile, Michael J.
• Primary Examiner(s): CUMMING, WILLIAM D
• Application Number:
  US09/396,137
• Time in Patent Office: 699 Days
• Field of Search: 455/3.1, 375/260, 348/12
• US Class Current: 725/106
• 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 bidirectional multipoint-to-point communications system for sending payload information over a distribution network is provided. The system includes a head-end terminal coupled to the distribution network to a plurality of service units. The head-end terminal includes a head-end controller for sending payload data to and from an external communications network and for producing and processing control messages at the head-end terminal, a head-end multicarrier transmitting modem coupled to the head-end controller for modulating downstream payload information and downstream control messages onto multiple orthogonal carriers spread throughout substantially all of a first frequency band, and a head-end multicarrier receiving modem coupled to the head-end controller for demodulating multiple orthogonal carriers spread throughout substantially all of a second frequency band and carrying upstream payload information and control messages. Each of the service units receives the downstream control messages and downstream payload information over only a portion of the first frequency band, and each of the service units transmitting only a portion of the upstream control messages and upstream payload information. Each of the service units includes a service-unit controller, a service-unit multicarrier receiving modem, and a service-unit multicarrier transmitting modem.

Claims

1. A bidirectional multipoint-to-point communications system for sending payload information over a distribution network, comprising:

a head-end tenninal coupled to the distribution network for transmitting downstream control messages and downstream payload information in a first frequency band, and for receiving upstream control messages and upstream payload information in a second frequency band, the head-end terminal including;

a head-end controller for sending the payload data to and from an external communications network and for producing and processing the control messages at the head-end terminal,

a head-end multicarrier transmitting modem coupled to the head-end controller for modulating the downstream payload information and the downstream control messages onto multiple orthogonal downstream carriers spread throughout substantially all of the first frequency band on the distribution network,

a head-end multicarrier receiving modem coupled to the head-end controller for demodulating multiple orthogonal upstream carriers spread throughout substantially all of the second frequency band and carrying the upstream payload information and control messages on the distribution network;

a plurality of service units physically remote from each other and from the head-end tenninal, each of the remote service units receiving the downstream control messages and downstream payload information over only a portion of the first frequency band, and each of the remote service units transmitting only a portion of the upstream control messages and upstream payload information, each of the remote service units including;

a service-unit controller for transferring a portion of the payload data to and from user equipment and for producing and processing the control messages at the remote service unit,

a service-unit multicarrier receiving modem coupled to the distribution network for demodulating only a portion of the multiple downstream orthogonal carriers, containing the portion of the the payload information and at least some of the control messages from the head-end transmitting modem,

a service-unit multicarrier transmitting modem coupled to the service-unit controller for modulating the portion of the upstream payload information and some of the upstream control messages onto multiple orthogonal upstream carriers in only a portion of the second frequency band on the distribution network.

2. The system of claim 1, wherein the multiple carriers are orthogonal frequency-division-multiplex carriers.

3. The system of claim 2, wherein the control messages occupy multiple control carriers within both the first and the second frequency bands.

4. The system of claim 3, wherein substantially all of the control carriers carry control messages for all of the remote service units.

5. The system of claim 3, wherein substantially all control messages include an address identifying at least one of the remote service units.

6. The system of claim 3, wherein the control carriers are substantially evenly spaced in frequency throughout the carriers carrying the downstream payload information.

7. The system of claim 3, wherein the control carriers are substantially evenly spaced in frequency throughout the carriers carrying the upstream payload information.

8. The system of claim 3, wherein the downstream carriers are disposed in a plurality of contiguous subbbands each containing a subset of the carriers containing the downstream payload information and at least one of the control carriers.

9. The system of claim 8, wherein the at least one control carrier occupies the middle of each of the subbands.

10. The system of claim 8, wherein the downstream receiving modem is capable of receiving only one of the subbands at any one time.

11. The system of claim 10, wherein the downstream receiving modem is tunable over a plurality of the subbands.

12. The system of claim 11, wherein the downstream modem is responsive to one of the control messages for tuning to a particular one of the subbands.

13. The system of claim 1, wherein the service-unit controller includes means for adjusting at least one parameter of the upstream transmitting modem so as to enhance the orthogonality of its carriers with respect to the carriers of others of the remote service units.

14. The system of claim 13, wherein the parameter-adjusting means adjusts the frequency of the upstream carriers.

15. The system of claim 13, wherein the parameter-adjusting means adjusts the timing of the payload information modulated on the upstream carriers.

16. The system of claim 15, wherein the parameter-adjusting means responds to the timing of the downstream control messages to adjust the timing of the payload information modulated on the upstream carriers.

17. The system of claim 13, wherein the parameter-adjusting means adjusts the amplitude of the upstream carriers.

18. The system of claim 1, wherein the downstream receiving modem of at least some of the remote service units is capable of receiving only a relatively small portion of the entire first frequency band at any one time.

19. The system of claim 18, wherein the downstream receiving modem responds to certain of the downstream control messages to tune to a particular one of a number of relatively small portions of the first frequency band.

20. The system of claim 18, wherein the downstream receiving modem of others of the remote service units is capable of receiving a relatively larger portion of the first frequency band at any one time.

21. The system of claim 1, wherein different ones of the downstream and upstream carriers are modulated differently.

22. The system of claim 20, wherein the control carriers and the payload carriers are modulated at different data rates.

23. The system of claim 21, wherein the control carriers are modulated at a substantially lower data rate than that of the payload carriers.

24. The system of claim 20, wherein the control carriers and the payload carriers are modulated by different modulation methods.

25. The system of claim 21, wherein one of the modulation methods is quadrature amplitude modulation.

26. The system of claim 24, wherein one of the modulation methods is phase-shift keying.

27. A head-end tenninal for a bidirectional multipoint-to-point multicarrier communications system for transmitting downstream payload information over a distribution network in a first frequency band to a plurality of service units physically remote from each other and from the head-end terminal and for simultaneously receiving upstream payload data from multiple ones of the remote service units in a second frequency band, wherein each of the remote service units includes:

a service-unit controller for transferring only a portion of the payload data to and from user equipment and for producing and processing control messages,

a service-unit multicarrier receiving modem coupled to the distribution network for demodulating only a subband of the first frequency band, the subband containing the portion of the the payload information and at least some of the control messages,

a service-unit multicarrier transmitting modem coupled to the service-unit controller for modulating the portion of the upstream payload information and some of the upstream control messages onto multiple upstream carriers in only a portion of the second frequency band on the distribution network,

the head-end terminal comprising;

a head-end controller for transferring the payload data to and from an external communications network and for producing downstream control messages for all of the remote service units and processing upstream control messages from all of the remote service units;

a head-end multicarrier transmitting modem coupled to the head-end controller for modulating the downstream payload information and the downstream control messages for all of the remote service units onto multiple orthogonal downstream carriers spread throughout substantially all of the first frequency band on the distribution network,

a head-end multicarrier receiving modem coupled to the head-end controller for demodulating multiple orthogonal upstream carriers spread throughout substantially all of the second frequency band and carrying the upstream payload information and control messages from all of the remote service units simultaneously.

28. A head-end terminal for a bidirectional multipoint-to-point multicarrier communications system for transmitting downstream payload information over a distribution network in a first frequency band to a plurality of service units physically remote from each other and from the head-end tenninal and for simultaneously receiving upstream payload data from multiple ones of the remote service units in a second frequency band, wherein each of the remote service units includes:

a service-unit controller for transferring only a portion of the payload data to and from user equipment and for producing and processing control messages,

a service-unit multicarrier receiving modem coupled to the distribution network for demodulating only a subband of the first frequency band, the subband containing the portion of the the payload information and at least some of the control messages,

a service-unit multicarrier transmitting modem coupled to the service-unit controller for modulating the portion of the upstream payload information and some of the upstream control messages onto multiple orthogonal upstream carriers in only one of a plurality of different subbands of the second frequency band on the distribution network,

the head-end terminal comprising;

a single head-end multicarrier receiving modem for demodulating multiple orthogonal upstream carriers in all of the different subbands spread throughout substantially all of the second frequency band and carrying the upstream payload information and control messages from all of the remote service units simultaneously;

a head-end controller coupled to the downstream receiving modem for transferring the payload data to and from an external communications network and for producing downstream control messages for all of the remote service units and processing upstream control messages from all of the remote service units;

a head-end multicarrier transmitting modem coupled to the head-end controller for modulating the downstream payload information and the downstream control messages for all of the remote service units onto multiple orthogonal downstream carriers spread throughout substantially all of the first frequency band on the distribution network.

29. A narrow-band service unit for a bidirectional multipoint-to-point communications system for receiving downstream payload information over a distribution network in a first frequency band from a head-end tenninal and for simultaneously transmitting upstream payload data to the head-end terminal in a second frequency band, wherein the head-end terminal includes:

a head-end controller for transferring the payload data to and from an external communications network, and for producing control messages for a plurality of the service units and processing control messages from a plurality of the service units,

a head-end multicanier transmitting modem coupled to the head-end controller for modulating the downstream payload information and the downstream control messages onto multiple orthogonal downstream carriers spread throughout substantially all of the first frequency band on the distribution network,

a head-end multicarrier receiving modem coupled to the head-end controller for demodulating multiple orthogonal upstream carriers spread throughout substantially all of the second frequency band and carrying the upstream payload information and control messages on the distribution network,

the service unit comprising;

a service-unit multicarrier receiving modem coupled to the distribution network for demodulating only a relatively small subband of the multiple downstream orthogonal carriers, the subband containing a portion of the the payload information and at least some of the control messages from the head-end transmitting modem;

a service-unit controller coupled to the downstream receiving modem for transferring a portion of the payload data to and from user equipment, and for processing only some of the downstream control messages and producing upstream control messages for the head-end terminal;

a service-unit multicarrier transmitting modem coupled to the service-unit controller for modulating the upstream payload information and the upstream control messages onto multiple orthogonal upstream carriers in only a relatively small portion of the second frequency band on the distribution network.