Method and apparatus for controlling access to a communication channel

• US 6,963,580 B2
• Filed: 02/16/2001
• Issued: 11/08/2005
• Est. Priority Date: 03/31/2000
• Status: Expired due to Fees

• Current Assignee: Clearwire Communications LLC (Deutsche Telekom AG), Clearwire Ip Holdings LLC (Deutsche Telekom AG)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Chien, Herman, Ho, Jin-Meng, Hong, Liang A., Leung, Kin K., Hoole, Elliott
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): PHAM, BRENDA H
• Application Number:
  US09/784,979
• Publication Number:
  US 20010043618A1
• Time in Patent Office: 1,726 Days
• Field of Search: 370/264, 370/310, 370/312, 370/314, 370/321, 370/322, 370/329, 370/336, 370/341, 370/347, 370/348, 370/335, 370/445, 370/431, 370/433, 370/437, 370/442, 370/447, 370/456, 370/458, 370/459, 370/461, 370/462, 370/464
• US Class Current: 370/445
• CPC Class Codes: H04B 7/2643 using time-division multiple access [TDMA] H04B7/2615, H04B7/2618 take precedence
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 84/14 WLL [Wireless Local Loop]; RLL [Radio Local Loop]

Abstract

A method and an apparatus provide for controlled access to a shared communication medium. Time slots on a forward channel include information regarding status useful for remote units to determine whether a reverse channel is available for seizure. Additionally, information along the forward channel provides guidance to the remote units to control attempts to seize the reverse channel. In one embodiment a remote unit divides a data package into a plurality of portions and attempts to seize the reverse channel using a single portion of the data package which corresponds to one time slot on the reverse channel. It then waits until it receives notification along the forward channel that the first data portion was successfully received before it attempts to send any of the remainder of its data in consecutive time slots on the reverse channel.

Claims

1. A method for enhancing data throughput in a fixed wireless communication system that includes a plurality of remote units, a base unit, a forward communication channel from the base unit to said plurality of remote units, and a shared reverse communication channel from said remote units to said base unit wherein each communication channel comprises a plurality of time slots, the method comprising the steps of:

at a first remote unit,

detecting an idle status indicator transmitted on a first time slot on said forward channel;

transmitting a first portion of a data package to said base unit on the reverse communication channel in a time slot following a detection of an idle status; and

monitoring an idle status indicator and a decode indicator in time slots along the forward channel after transmitting said first portion;

at the base unit,

receiving data in a time slot from the reverse channel;

attempting to decode the received data;

in a time slot along the forward channel,

changing an idle status indicator to indicate a busy state;

setting a decode indicator to reflect whether the decoding attempt was successful; and

transmitting said time slot along the forward channel,

wherein when said first remote unit receives a round trip time slot that occurs at a round-trip time after transmitting the first portion and said round trip time slot has an idle status indicator that indicates a busy status and a decode indicator that indicates that the base unit successfully decoded said first portion, said first remote unit transmits a remainder of said data package in a plurality of subsequent time slots.

2. The method of claim 1 wherein at a second remote unit steps include,

detecting an idle status indicator transmitted on a second time slot, that follows said first time slot on said forward channel;

transmitting a first portion of a second data package to said base unit on the reverse communication channel in a time slot that follows the time slot used by the first portion transmitted by said first remote unit;

monitoring the idle status indicator and decode indicator in time slots after transmitting said first portion of said second data package;

detecting that said base unit has changed its idle status in the round trip slot associated with the first remote unit; and

in response to said detecting of a change in idle status, delaying transmission of a remainder of said second data package even if said first portion of said second data package was successfully received by said base unit.