Multicarrier transmission system with low power sleep mode and rapid-on capability

• US 7,978,753 B2
• Filed: 11/10/2009
• Issued: 07/12/2011
• Est. Priority Date: 01/26/1998
• Status: Expired due to Fees

• Current Assignee: TQ Delta LLC (Techquity Capital Management, LLC)
• Original Assignee: Aware Incorporated (Crowley Holdings Preferred LLC)
• Inventors: Greszczuk, John A., Gross, Richard W., Padir, Halil, Tzannes, Michael A.
• Primary Examiner(s): Tran, Khai
• Application Number:
  US12/615,946
• Publication Number:
  US 20100054312A1
• Time in Patent Office: 609 Days
• Field of Search: 375/219, 375/220, 375/260, 375/222, 375/356, 375/282, 375/503, 375/373, 375/376, 370/311, 370/278, 370/282, 370/503, 455/551, 455/560, 455/574, 455/572, 455/500
• US Class Current: 375/219
• CPC Class Codes: H04B 1/40 Circuits
• CPC Class Codes: H04L 12/12 Arrangements for remote connection or disconnection of substations or of equipment thereof
• CPC Class Codes: H04L 12/40006 Architecture of a communication node current supply arrangements H04L12/10; intermediate storage or scheduling H04L49/90
• CPC Class Codes: H04L 12/40169 Flexible bus arrangements arrangements for maintenance or administration involving management of faults; events, alarms H04L41/06; automatic restoration of network faults H04L41/0654
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04M 11/06 Simultaneous speech and data transmission, e.g. telegraphic transmission over the same conductors
• CPC Class Codes: H04W 52/0235 where the received signal is a power saving command
• CPC Class Codes: H04W 52/0241 where no transmission is received, e.g. out of range of the transmitter
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A multicarrier transceiver is provided with a sleep mode in which it idles with reduced power consumption when it is not needed to transmit or receive data. The full transmission and reception capabilities of the transceiver are quickly restored when needed, without requiring the full (and time-consuming) initialization commonly needed to restore such transceivers to operation after inactivity.

Claims

1. A multicarrier transceiver having a sleep mode capability, comprising

A. means responsive to a sleep mode command for:

(1) storing selected state parameters characteristic of the communications channel over which the transceiver is operating; and

(2) reducing power to selected portions of transceiver circuitry;

and

B. means responsive to a wake-up command for;

(1) restoring power to said transceiver;

(2) restoring the state of said transceiver from said sleep mode by means of said stored parameters; and

C. means for maintaining a common, synchronized data frame count between said transceiver and a remote transceiver with which it communicates, to thereby facilitate restoration of communication without reinitialization of said transceiver, wherein the state parameters include one or more parameters selected from the group comprising frequency-domain equalizer coefficients, time-domain equalizer coefficients, echo canceller coefficients, bit allocations, coding parameters, fine gains, and subchannel gains.

2. A multicarrier transceiver according to claim 1 in which the means for maintaining said frame count comprises a signal defining a timing reference during at least the time when said first transceiver is in sleep mode.

3. A multicarrier transceiver according to claim 2 in which said signal comprises a pilot tone transmitted from one transceiver to another with which it is in communication.

4. A multicarrier transceiver according to claim 3 in which said pilot tone is transmitted between said transceivers during both normal operation and reduced power operation.

5. A multicarrier transceiver according to claim 1 in which maintaining synchronization includes maintaining synchronization of frame counters between said transceivers.

6. A multi carrier transceiver according to claim 5 in which maintaining synchronization further includes maintaining synchronization of the phase of a synchronizing signal transmitted between said transceivers.

7. A multicarrier transceiver according to claim 1 including means to transmit an idle symbol to said remote transceiver when said transceiver is in sleep mode.

8. A multicarrier transceiver according to claim 1 including means to transmit to said remote transceiver a short test signal on awaking from sleep mode in order to determine whether transmission conditions have changed sufficiently during sleep mode to require reinitialization of said transceiver on emerging from sleep mode.

9. A method of providing a sleep mode in a multicarrier transceiver characterized by a plurality of state parameters characteristic of the communications channel over which the transceiver is operating and requiring initialization of said parameters for normal communications, comprising the steps of:

A. storing selected ones of said state parameters in response to a sleep mode command;

B. reducing power to selected portions of the circuitry following said storing;

C. restoring power to said selected portions in response to an awaken signal; and

D. restoring the state of said transceiver from said stored parameters in response to said wakeup signal to thereby obviate reinitialization of said transceiver, wherein the state parameters include one or more parameters selected from the group comprising frequency-domain equalizer coefficients, time-domain equalizer coefficients, echo canceller coefficients, bit allocations, coding parameters, fine gains, and subchannel gains.

10. A method according to claim 9 including the step of maintaining synchronization in said transceiver with a synchronization signal transmitted to said transceiver during the time that said transceiver is in sleep mode.