System and method for asynchronous communications employing direct and indirect access protocols

• US 7,133,398 B2
• Filed: 03/27/2002
• Issued: 11/07/2006
• Est. Priority Date: 03/27/2002
• Status: Active Grant

• Current Assignee: ARRIS Enterprises LLC (CommScope Holding Company, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Callaway, Jr., Edgar Herbert, Brown, Monique Bourgeois, Korfhage, Stephen Raphael, Allen, Vernon Anthony
• Primary Examiner(s): Ngo, Ricky Q.
• Assistant Examiner(s): Wong, Warner
• Application Number:
  US10/108,116
• Publication Number:
  US 20030185170A1
• Time in Patent Office: 1,686 Days
• Field of Search: 370/356, 370503-520, 370310-350, 375/356
• US Class Current: 370/350
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A communication access protocol improves the accessibility of devices operating on an asynchronous network (100), while supporting reduced power consumption. The network (100) includes a mediation device (130) for facilitating communications among network devices. Generally, each network device periodically transmits beacon signals to advertise its presence, and listens for communication signals targeted at the network device (532, 534). A device initiating communication with another operates in one of at least two operating modes in order to establish communications (536, 537, 538). In one mode, the initiating device communicates with the mediation device in order to derive timing information for the other device (537). In another mode, the initiating device listens to receive beacon signals directly from the target device in order to synchronize communications with the device (538). The selection of one of the two operating modes depends on a control parameter established for the initiating device, which in one embodiment is dependent on the urgency of communication, a maximum number of retries for using the mediation device, or the like.

Claims

1. A method for establishing communication in an asynchronous network having first and second communication devices and a mediation device for facilitating communications among asynchronously operating communication devices, the method comprising the steps of:

asynchronously transmitting a communication request;

operating in one of first and second operating modes based on a control parameter;

asynchronously communicating with the mediation device in order to ascertain timing information in order to synchronize communications with a first communication device, when operating in the first operating mode;

listening to receive beacon signals directly from the first communication device in order to synchronize communications with the first communication device, when operating in the second operating mode;

after synchronizing, communicating between the first and the second communication device without further use of the mediation device to relay any communications between the first and the second communication device;

determining whether there is a response to the communication request according to a particular criteria;

when there is no response to the communication request according to the particular criteria, operating in the second operating mode; and

wherein the step of communicating with the mediation device further comprises the step of transmitting a communication request to the mediation device which communication request includes information concerning the first communication device.

2. The method of claim 1, wherein the step of transmitting a communication request comprises the step of encoding the communication request in a beacon signal.

3. The method of claim 1, further comprising the steps of, at the second communication device:

accessing the control parameter to determine a maximum number of times for transmitting the communication request without receiving a corresponding response from the mediation device;

determining that there is no response to the communication request according to the particular criteria when no corresponding response is received to the communication request after transmitting the communication request the maximum number of times.

4. The method of claim 1, further comprising the steps of:

at the mediation device;

receiving a beacon signal from the first communication device;

generating timing information for communication with the first communication device in response to receipt of the beacon signal;

receiving a communication request from the second communication device;

transmitting the timing information to the second communication device in response to the communication request.

5. A method for establishing communication in an asynchronous network having first and second communication devices and a mediation device for facilitating communications among asynchronously operating communication devices, the method comprising the steps of:

at the first communication device, periodically transmitting beacon signals using a communication frame having a transmit slot immediately followed by a receive slot;

at the second communication device;

periodically transmitting a beacon signal using a communication frame having a transmit slot immediately followed by a receive slot;

initiating communication with the first communication device, including the steps of;

(a) transmitting to the mediation device, a beacon signal that contains a communication request, the communication request including information concerning the first communication device;

(b) listening for a response from the mediation device to the communication request;

(c) upon receiving a response to the communication request, communicating with the first communication device using timing information derived from the response; and

(d) upon receiving no response to the communication request, listening for beacon signals directly from the first communication device in order to synchronize communications with the first communication device.

6. The method of claim 5, further comprising the step of, at the second communication device, executing steps (a) and (b) a maximum number of times as established by a control parameter, prior to executing step (d).

7. The method of claim 6, further comprising the steps of:

at the mediation device;

receiving a beacon signal from the first communication device;

generating timing information for communication with the first communication device in response to receipt of the beacon signal;

receiving a communication request from the second communication device;

transmitting the timing information to the second communication device in response to the communication request.

8. A method of communication in an asynchronous network between an initiating device and a target device, the network having a mediation device for facilitating communications among asynchronously operating communication devices, the method comprising the steps of:

at the initiating device;

transmitting a communication request, targeted at the mediation device, for information needed to ascertain timing information pertaining to the target device in order to synchronize communications with the target device;

determining whether there is a response to the communication request according to a particular criteria;

when there is no response to the communication request according to the particular criteria, operating in a listening mode to receive beacon signals directly from the target device in order to synchronize communications with the target device; and

when there is a response to the communication request according to the particular criteria, synchronizing communications with the target device using timing information derived from the response.

9. The method of claim 8, further comprising the steps of:

at the target device, periodically waking up from a sleep mode to transmit beacon signals and to listen for a response signal; and

at the mediation device;

receiving a beacon signal from the target device;

generating timing information for communication with the target device in response to receipt of the beacon signal;

receiving a communication request from the initiating device;

transmitting the timing information to the initiating device in response to the communication request.

10. A method of asynchronously communicating with a target wireless device, comprising:

occasionally entering a first wake up mode from a default sleep mode to transmit a beacon signal and to listen for device transmissions;

entering a second wake up mode to transmit a message to a target wireless device, and during the second wake up mode;

transmitting a communication request concerning the target wireless device to a mediation device that facilitates communication among asynchronously operating communication devices;

listening for a response to the communication request from the mediation device;

upon obtaining a response according to a predefined criteria, communicating with the target wireless device using timing information contained within the response;

upon not obtaining a response according to the predefined criteria, entering an active wait mode to receive communication directly from the target wireless device;

reverting to the default sleep mode upon termination of either the first or the second wake up mode.