US5987023A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transmission timing control in digital radio telephony
Assignee: Nortel Networks Ltd
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Filing: 1995-09-08
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Granted: 1999-11-16
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Expires: 2015-09-08
Abstract
Abstract In time domain multiplex/time domain multiple access communications between a base station and subscriber unit, the base station sends a timing reference signal. A subscriber unit responds with a data packet (a) sufficiently short to ensure correct reception by the base irrespective of transmission time. The base determines the transmission time taken and instructs the subscriber unit to advance its timings so that longer data packets (b) can be sent so as to be received when expected. The timing adjustment includes both a fixed present component dependent on approximate separation of base station and subscriber unit, and a second component from measurement of the transmission time taken.
Inventors
- 👤 Richard John Albrow
- 👤 Simon Alexander Black
- 👤 Leigh Carter
- 👤 Rupert Leslie Alexander Goodings
- 👤 Paul Maxwell Martin
- 👤 Neil Philip Piercy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:28
CPC Classifications
H; H04; H04J; H04J3/00; H04J3/02; H04J3/06; H04J3/0635; H04J3/0682; H04B; H04B7/00; H04B7/24; H04B7/26; H04B7/2662; H04B7/2671; H04B7/2678; H04B7/2681; H04W; H04W56/00; H04W56/003; H04W56/0055; H04W56/0065; H04W88/00; H04W88/08
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
153 words
A method of controlling the timing of transmissions of data packets from at least one first transmitting and receiving unit (NTE) to a second transmitting and receiving unit (BTE) in predetermined time slots within fixed length time frames, the second unit transmitting a timing reference signal to a first unit, the first unit transmitting in response a relatively short first packet at a time dependent on a preset first value, the first value being a predetermined estimate of the propagation delay dependent on the approximate separation of the first unit and the second unit, the second unit determines a second value dependent upon the actual propagation delay from the time of reception of the first packet, and the second unit transmits an adjustment signal dependent upon at least the second value to the first unit to adjust the timing of subsequent transmissions of relatively long packets from the first unit in response thereto.
Claim 2
Independent Claim
153 words
A method of controlling the timing of transmissions of data packets from at least one first transmitting and receiving unit (NTE) to a second transmitting and receiving unit (BTE) in predetermined time slots within fixed length time frames, the second unit transmitting a timing reference signal to a first unit, the first unit transmitting in response a relatively short first packet at a time dependent on a preset first value, the first value being a predetermined estimate of the propagation delay dependent on the approximate separation of the first unit and the second unit, the second unit determines a second value dependent upon the actual propagation delay from the time of reception of the first packet, and the second unit transmits an adjustment signal dependent upon at least the second value to the first unit to adjust the timing of subsequent transmissions of relatively long packets from the first unit in response thereto.
Claim 3
Dependent Claim
45 words
A method of controlling the timing of transmissions according to claim 1, in which the timing adjustment signal for a first unit includes a first component which is representative of the second value and a second component which is representative of the preset first value.
Claim 4
Dependent Claim
41 words
A method of controlling the timing of transmissions according to claim 2, in which once the first component is determined, the adjustment signal is sent to the first unit to set the timing adjustment to be used for subsequent information packets.
Claim 5
Dependent Claim
18 words
A method of controlling the timing of transmissions according to claim 1, in which transmissions are by radio.
Claim 6
Dependent Claim
33 words
A method of controlling the timing of transmissions according to claim 1, in which each first unit comprises a subscriber unit at a fixed location and the second unit is a base station.
Claim 7
Dependent Claim
25 words
A method of controlling the timing of transmissions according to claim 1, in which the first packet contains system control data and/or short information messages.
Claim 8
Dependent Claim
30 words
A method of controlling the timing of transmissions according to claim 1, in which the relatively long packets contain both system control data and other information, such as user data.
Claim 9
Dependent Claim
51 words
A method of controlling the timing of transmissions according to claim 1, in which first packets are sent repeatedly over a period of time for reception by the second unit so as to enable correct determination of a timing adjustment should the first one of the first packets not be received.
Claim 10
Dependent Claim
21 words
A method according to claim 8, in which a subsequent one of the first packets is sent at a different frequency.
Claim 11
Dependent Claim
178 words
Timing control means for controlling the timing of transmission of data packets from a first transmitting and receiving unit (NTE) to a second transmitting and receiving unit (BTE) in predetermined time slots within fixed length time frames, the second unit comprising timing reference signal transmission means, and the first unit comprising response means operative to transmit in response to receipt of a timing reference signal a relatively short first packet at a time dependent on a preset first value, the first value being a predetermined estimate of the propagation delay dependent on the approximate separation of the first unit and the second unit, the second unit further comprising determination means operative to determine a second value dependent upon the actual propagation delay from the time of reception of the first packet, and the second unit further comprising controlling means operative to transmit an adjustment signal dependent upon at least the second value to the first unit, the first unit further comprising adjustment means operative to adjust the timing of subsequent transmissions of relatively long packets in response thereto.
Claim 12
Dependent Claim
178 words
Timing control means for controlling the timing of transmission of data packets from a first transmitting and receiving unit (NTE) to a second transmitting and receiving unit (BTE) in predetermined time slots within fixed length time frames, the second unit comprising timing reference signal transmission means, and the first unit comprising response means operative to transmit in response to receipt of a timing reference signal a relatively short first packet at a time dependent on a preset first value, the first value being a predetermined estimate of the propagation delay dependent on the approximate separation of the first unit and the second unit, the second unit further comprising determination means operative to determine a second value dependent upon the actual propagation delay from the time of reception of the first packet, and the second unit further comprising controlling means operative to transmit an adjustment signal dependent upon at least the second value to the first unit, the first unit further comprising adjustment means operative to adjust the timing of subsequent transmissions of relatively long packets in response thereto.
Claim 13
Dependent Claim
44 words
Timing control means according to claim 10, in which the controlling means transmits an adjustment signal including a first component and a second component, the first component being representative of the second value and the second component being representative of the preset first value.
Claim 14
Dependent Claim
28 words
Timing control means according to claim 10, in which the second unit comprises a base station and the first unit comprises a subscriber unit at a fixed location.
Claim 15
Independent Claim
148 words
A method of adjustment of timing of up-link and down-link packets sent in time slots within fixed length time frames, including the steps of sending a reference signal from a base station, receiving the reference signal at a subscriber unit, sending a relatively short first packet from the subscriber unit in response to said reference signal, the relatively short first packet being sent at a time dependent on a preset value, the preset value being a predetermined estimate of the propagation delay dependent on the approximate separation of the subscriber unit and the base station, receiving the first packet at the base station, the base station determining a timing adjustment by measuring the timing of receipt of said first packet, and the base station transmitting an adjustment signal dependent upon said timing adjustment to the subscriber unit to adjust its timing of subsequent transmissions of relatively long packets.
Claim 16
Independent Claim
148 words
A method of adjustment of timing of up-link and down-link packets sent in time slots within fixed length time frames, including the steps of sending a reference signal from a base station, receiving the reference signal at a subscriber unit, sending a relatively short first packet from the subscriber unit in response to said reference signal, the relatively short first packet being sent at a time dependent on a preset value, the preset value being a predetermined estimate of the propagation delay dependent on the approximate separation of the subscriber unit and the base station, receiving the first packet at the base station, the base station determining a timing adjustment by measuring the timing of receipt of said first packet, and the base station transmitting an adjustment signal dependent upon said timing adjustment to the subscriber unit to adjust its timing of subsequent transmissions of relatively long packets.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-11-15 | 2003-05-17 | 2003-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-11-15 | 2007-05-17 | 2007-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-11-15 | 2011-05-17 | 2011-11-16 | $7700.00 | Window Closed / Lapsed |