Network slot synchronization scheme for a computer network communication channel

• US 7,324,544 B1
• Filed: 02/18/2003
• Issued: 01/29/2008
• Est. Priority Date: 09/11/1998
• Status: Expired due to Term

• Current Assignee: Cirrus Logic Incorporated
• Original Assignee: Cirrus Logic Incorporated
• Inventors: Gubbi, Rajugopal, Sevastian, Donia, EKAMBARAM, NATARAJAN, Patra, Nirmalendu Bikash
• Primary Examiner(s): Flynn, Nathan
• Assistant Examiner(s): SIDDIQI, MOHAMMAD A
• Application Number:
  US10/368,652
• Time in Patent Office: 1,806 Days
• Field of Search: 709/218, 709/220, 709225-227, 709/232, 709/224, 709/229, 370/278, 370/339, 370/330, 370/341, 370/431, 370/455, 370/509, 370/510, 370/442, 370/462, 455/450
• US Class Current: 370/442
• CPC Class Codes: H04J 3/16 in which the time allocation to individual channels within a transmission cycle is variable, e.g. to accommodate varying complexity of signals, to vary number of channels transmitted H04J3/17, H04J3/24 take precedence
• CPC Class Codes: H04L 1/16 in which the return channel carries supervisory signals, e.g. repetition request signals
• CPC Class Codes: H04L 12/28 characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks] wireless communication networks H04W ; arrangements for dividing the transmission path H04W40/00
• CPC Class Codes: H04L 12/2803 Home automation networks
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
• CPC Class Codes: H04L 12/56 Packet switching systems
• CPC Class Codes: H04L 63/126 the source of the received data
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04W 28/20 Negotiating bandwidth
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management

Abstract

Synchronization within a common communication channel having designated transmission time slots for various devices of a computer network is maintained by allowing transmissions within the channel outside of a network device'"'"'s designated time slot when a clear channel assessment indicates that a previous time slot is not being utilized by its associated device and/or upon receipt of an indication of the end of a transmission of another device in the network. The clear channel assessment preferably takes into account the device'"'"'s designated transmission time slot within the communication channel with respect to those of other network devices and may be a time period that is the product of a predetermined clear channel waiting time and a numerical representation of the device'"'"'s designated transmission time slot within the communication channel with respect to those of other network devices. The clear channel waiting time itself may be specified by a network master device as part of a network connection process. The network device may be configured to construct one or more packets for transmission within the network in advance of its designated time slot to accommodate these early transmissions.

Claims

1. A method for efficiently utilizing bandwidth in a wireless network including a server and one client and another client, wherein data transmission across a data communications channel in the network is organized into frames including a plurality of time slots, wherein one time slot is assigned to the one client and another time slot is assigned to the another client, and wherein the one time slot precedes the another time slot within a frame, the method comprising:

at the another client, monitoring the one time slot to determine whether the one client is transmitting data to the server in the one time slot of a current frame;

waiting at the another client for a predetermined time interval that is a product of a clear channel assessment time and the number of time slots between the one time slot and the another time slot; and

after the predetermined time interval, transmitting data from the another client to the server during the one time slot in the current frame responsive to a determination that the one client is not transmitting during the one slot in the current frame.

2. The method of claim 1, wherein the one time slot is a fixed time slot.

3. The method of claim 1, further comprising pre-assembling at least one data packet in advance at the another client such that the at least one data packet is available for transmission during the one time slot.

4. The method of claim 3, further comprising triggering pre-assembly of the at least one data packet in response to an early transmission timer maintained by the another client.

5. The method of claim 1, further comprising specifying the clear channel assessment time with the server.

6. The method of claim 5, wherein the clear channel assessment time is specified by the server at connection time of the another client.

7. The method of claim 1, wherein the frames of a plurality of time slots are transmitted on a transmission channel and the method further comprises selecting the channel from a plurality of channels with the server.

8. The method of claim 7, wherein the channel comprises a spread spectrum channel defined by a frequency band and a pseudo-random code.

9. The method of claim 7, further comprising searching for an available channel with the server for selection as the transmission channel.

10. The method of claim 1, wherein the clear channel assessment time is specified by the server in a connection agreement with the another client.

11. The method of claim 1, wherein the server assigns the one time slot in a connection agreement with the one client.