Apparatus, method, and computer program product for wireless networking using directional signaling

• US 7,075,902 B2
• Filed: 11/12/2002
• Issued: 07/11/2006
• Est. Priority Date: 02/11/2002
• Status: Expired due to Fees

• Current Assignee: HRL Laboratories LLC (The Boeing Co.)
• Original Assignee: HRL Laboratories LLC (The Boeing Co.)
• Inventors: El Batt, Tamer
• Primary Examiner(s): Jung, Min
• Application Number:
  US10/293,213
• Publication Number:
  US 20030152086A1
• Time in Patent Office: 1,337 Days
• Field of Search: 370/445, 370/310, 455/25, 342/350, 342/367
• US Class Current: 370/310
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 74/0816 with collision avoidance
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

The present invention provides a method, apparatus, and a computer program product for selective directional wireless communication. The apparatus comprises a computer system with a directional communication module. The present invention takes advantage of directional antennas in order to optimize wireless communication by minimizing interference with neighboring nodes. The technique presented is a CSMA/CA-based reservation protocol that improves the multiple access throughput of a wireless ad-hoc network by efficiently utilizing the interference reduction feature of switched-beam antennas by balancing the number of neighbors that need to back-off and the number of control/data packet collisions.

Claims

1. An apparatus for selective directional wireless communication comprising a computer system including a processor, a memory coupled with the processor, a directional communication module, connected with the processor, for receiving communication signals and for transmitting communication signals in any of a plurality of directions which may be blocked or unblocked, and wherein the computer system further comprises means, residing in its processor and memory, for:

storing information including identities of and directions to each neighbor node, and an identity of the apparatus;

transmitting in all unblocked directions, via the directional communication module, a request-to-send signal including a source node identity and a destination node identity, with the source node identity consisting of the identity of the apparatus, the request-to-send signal indicating a start of a transmission;

receiving, via the directional communication module, a clear-to-send signal corresponding to a transmitted request-to-send signal indicating whether to start a data transmission;

transmitting, when indicated to do so by the clear-to-send signal, a data transmission corresponding to the transmitted request-to-send signal, in the direction corresponding to the destination node identity;

receiving, an acknowledgement signal upon completion of the data transmission;

receiving, via the directional communication module, a request-to-send signal including a source node identity and a destination node identity, and determining whether the apparatus is the destination node;

determining after receipt of a request-to-send signal, and when the apparatus is not the destination node, whether the source node or the destination node are within a communication range of the apparatus, and when the source node is within the communication range of the apparatus, blocking communication signals in the direction of the source node for a predetermined period of time; and

when the destination node is within the communication range of the apparatus, blocking communication signals in the direction of the destination node for a predetermined period of time;

transmitting in all unblocked directions, when the apparatus is the destination node, a clear to send signal corresponding to a transmitted request-to-send signal indicating whether to transmit a data transmission;

receiving, when a data transmission was permitted by the transmitted clear-to-send signal, a data transmission corresponding to the received request-to-send signal; and

transmitting in all unblocked directions, an acknowledgement signal either upon completion of the data transmission or after sending a clear-to-send signal indicating not to send a data transmission.

2. An apparatus for selective directional wireless communication as set forth in claim 1, wherein the directional communication module is selected from a group consisting of radio frequency antennas and infrared transceivers.

3. An apparatus for selective directional wireless communication as set forth in claim 1, wherein the information stored further comprises an index of a directional beam to be used during data transmission and acknowledgement transmission, and an index of a directional beam used by a transmitting neighbor during channel reservation.

4. A method for selective directional wireless communication, the method operating on a computer system including a processor, a memory coupled with the processor, a directional communication module, connected with the processor, receiving communication signals and for transmitting communication signals directionally over any of a plurality of directions which may be blocked or unblocked, wherein the method comprises steps of:

storing information including identities of and directions to each neighbor node, and an identity of the current node;

transmitting in all unblocked directions, via the directional communication module, a request-to-send signal including a source node identity and a destination node identity, with the source node identity consisting of an identity of the apparatus, the request-to-send signal indicating a start of a transmission;

receiving, via the directional communication module, a clear-to-send signal corresponding to a transmitted request-to-send signal indicating whether to start a data transmission;

transmitting, when indicated to do so by the clear-to-send signal, a data transmission corresponding to the transmitted request-to-send signal, in the direction corresponding to the destination node identity;

receiving, an acknowledgement signal upon completion of the data transmission;

receiving, via the directional communication module, a request-to-send signal including a source node identity and a destination node identity, and determining whether the apparatus is the destination node;

determining after receipt of a request-to-send signal, and when the apparatus is not the destination node, whether the source node or the destination node are within a communication range of the apparatus, and when the source node is within the communication range of the apparatus, blocking communication signals in the direction of the source node for a predetermined period of time; and

when the destination node is within the communication range of the apparatus, blocking communication signals in the direction of the destination node for a predetermined period of time;

transmitting in all unblocked directions, when the apparatus is the destination node, a clear to send signal corresponding to a transmitted request-to-send signal indicating whether to transmit a data transmission;

receiving, when a data transmission was permitted by the transmitted clear-to-send signal, a data transmission corresponding to the received request-to-send signal; and

transmitting in all unblocked directions, an acknowledgement signal either upon completion of the data transmission or after sending a clear-to-send signal indicating not to send a data transmission.

5. A method for selective directional wireless communication as set forth in claim 4, wherein the directional communication module used in the performance of the method is selected from a group consisting of radio frequency antennas and infrared transceivers.

6. A method for selective directional wireless communication as set forth in claim 4, wherein the information stored in the information storing step further comprises an index of a directional beam to be used during data transmission and acknowledgement transmission, and an index of a directional beam used by a transmitting neighbor during channel reservation.

7. A computer program product for selective directional wireless communication, the computer program product comprising computer readable instructions on a computer-readable medium to be used on an apparatus including computer system including a processor, a memory coupled with the processor, a directional communication module, connected with the processor, receiving communication signals and for transmitting communication signals directionally over any of a plurality of directions which may be blocked or unblocked, and wherein the computer program product comprises means, stored on a computer readable medium, for:

storing information including identities of and directions to each neighbor node, and an identity of the current node;

transmitting in all unblocked directions, via the directional communication module, a request-to-send signal including a source node identity and a destination node identity, with the source node identity consisting of an identity of the apparatus, the request-to-send signal indicating a start of a transmission;

receiving, via the directional communication module, a clear-to-send signal corresponding to a transmitted request-to-send signal indicating whether to start a data transmission;

transmitting, when indicated to do so by the clear-to-send signal, a data transmission corresponding to the transmitted request-to-send signal, in the direction corresponding to the destination node identity;

receiving, an acknowledgement signal upon completion of the data transmission;

receiving, via the directional communication module, a request-to-send signal including a source node identity and a destination node identity, and determining whether the apparatus is the destination node;

determining after receipt of a request-to-send signal, and when the apparatus is not the destination node, whether the source node or the destination node are within a communication range of the apparatus, and when the source node is within the communication range of the apparatus, blocking communication signals in the direction of the source node for a predetermined period of time; and

when the destination node is within the communication range of the apparatus, blocking communication signals in the direction of the destination node for a predetermined period of time;

transmitting in all unblocked directions, when the apparatus is the destination node, a clear to send signal corresponding to a transmitted request-to-send signal indicating whether to transmit a data transmission;

receiving, when a data transmission was permitted by the transmitted clear-to-send signal, a data transmission corresponding to the received request-to-send signal; and

transmitting in all unblocked directions, an acknowledgement signal either upon completion of the data transmission or after sending a clear-to-send send signal indicating not to send a data transmission.

8. A computer program product for selective directional wireless communication as set forth in claim 7, wherein the directional communication module is selected from a group consisting of radio frequency antennas and infrared transceivers.

9. A computer program product for selective directional wireless communication as set forth in claim 8, wherein the information stored further comprises an index of a directional beam to be used during data transmission and acknowledgement transmission, and an index of a directional beam used by a transmitting neighbor during channel reservation.