Methods and apparatus for network joining using a multiple message per TDMA control slot methodology

• US 7,583,641 B2
• Filed: 05/23/2006
• Issued: 09/01/2009
• Est. Priority Date: 05/23/2006
• Status: Expired due to Fees

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Lord, Bruce J.
• Primary Examiner(s): Shah; Chirag G
• Assistant Examiner(s): Shivers; Ashley L
• Application Number:
  US11/419,926
• Publication Number:
  US 20070274346A1
• Time in Patent Office: 1,197 Days
• Field of Search: 370/314, 370/321, 370/326, 370/330, 370/336, 370/337, 370/347, 370/431, 370/436, 370/442, 370/443, 370/230.1, 370/468, 342/25.D, 342/25.E, 342/140, 33/202, 332/90, 332/93
• US Class Current: 370/337
• CPC Class Codes: H04B 7/2656 for structure of frame, burst

Abstract

A method for transmitting network joining message packets during control slots of a time division multiple access (TDMA) frame sequence is described. The method includes determining a size of the network joining packet to be processed for transmission, recognizing which slots of the TDMA frame sequence are control slots, subdividing the control slots based on at least one of the size of the network joining packet and a data rate of a control slot queue, and transmitting a number of the network joining message packets during the control slot of the TDMA frame sequence, the number of transmitted based on the subdivision of the control slots.

Claims

1. A method for transmitting network joining message packets from a network device during control slots of a time division multiple access (TDMA) frame sequence, said method comprising:

determining a size of the network joining packet to be processed for transmission;

recognizing which slots of the TDMA frame sequence are control slots;

subdividing the control slots based on at least one of the size of the network joining packet and a data rate of a control slot queue;

associating a line of sight azimuth, an elevation, and a range with a first network joining message packet;

incrementing at least one of the line of sight azimuth, the elevation, and the transmission range for association with each subsequent network joining message packet; and

transmitting, from the network device, a number of the network joining message packets during the control slot of the TDMA frame sequence, the number of network joining message packets transmitted based on the subdivision of the control slots.

2. A method according to claim 1 further comprising interrogating a header of a received message packet to determine if the packet is a network joining message packet.

3. A method according to claim 1 wherein recognizing which slots of the TDMA frame sequence are control slots comprises:

randomly determining if the network joining message packets are to be transmitting during a first control slot or a second control slot of a TDMA frame sequence; and

designating the remaining control slot for reception of network joining message packets from other transmitting nodes.

4. A method according to claim 1 wherein associating a line of sight azimuth, an elevation, and a range with a first network joining message packet comprises setting a lowest possible line of sight azimuth, elevation, and transmission range for a first network joining message packet transmission.

5. A method according to claim 1 wherein transmitting a number of the network joining packets further comprises:

a) setting a lowest possible line of sight azimuth, elevation, and transmission range for a first network joining message packet transmission;

b) incrementing the line of sight azimuth by one 3 dB antenna beam width for subsequent network joining message packet transmissions until an extent for the line of sight azimuth is reached;

c) resetting the line of sight azimuth to the lowest possible value;

d) incrementing the elevation by one 3 dB antenna beam width for subsequent network joining message packet transmissions;

e) repeating steps b) through e), until an extent for the elevation is reached;

f) resetting the line of sight azimuth and elevation to the lowest possible value;

g) incrementing the transmission range for subsequent network joining message packet transmissions;

h) repeating steps b) through g) until a maximum line of sight azimuth, a maximum elevation, and a maximum transmission range is reached; and

j) initiating routing protocol network communications in TDMA non-control data slots if a network response message has been received.

6. A method according to claim 3 further comprising defocusing a beam of a phased array antenna beam to emulate an omni-directional antenna for the field of regard of the phased array antenna.

7. A method according to claim 1

wherein incrementing at least one of the line of sight azimuth, the elevation, and the transmission range for association with each subsequent network joining message packet comprises incrementing at least one of line of sight azimuth and elevation by one-half a 3 dB beam width for a subsequent network joining message packet transmission.

8. A method according to claim 1 wherein transmitting a number of the network joining message packets during the control slot of the TDMA frame sequence comprises transmitting the network joining message packets using a beam from a phased array antenna.

9. A method according to claim 1 wherein subdividing the control slots comprises:

calculating a message packet transmit time as the size of the message packet divided by a transmission data rate; and

calculating a message flight time as a transmission range divided by the speed of light.

10. A method according to claim 9 further comprising pointing a beam of a phased array antenna at an assigned azimuth and elevation for a duration of the combination of the packet transmit time and the message flight time.

11. A method according to claim 1 wherein transmitting a number of the network joining message packets during the control slot of the TDMA frame sequence comprises transmitting network joining message packets until a guard time associated with the control slot occurs.

12. A method according to claim 1 wherein said method is initiated utilizing a standard routing protocol.

13. A network device comprising:

a processor programmed with a message routing protocol, a link layer, and a media access (MAC) layer;

a transmitter configured to receive network joining message packets from said processor; and

an antenna operable to transmit at least network joining message packets received from said transmitter, said link layer configured to set a line of sight azimuth, elevation, and transmission range for a field of regard for said antenna for a first network joining message packet transmission and increment at least one of line of sight azimuth, elevation, and range for each subsequent network joining message packet transmission, said network device programmed to transmit multiple network joining message packets during a control slot of a time division multiple access (TDMA) frame sequence.

14. A network device according to claim 13 wherein said link layer is configured to determine whether a message received from said message routing protocol is a network joining message packet.

15. A network device according to claim 14 wherein said link layer is configured to randomly determine if the network joining message packet is to be transmitting during a first control slot or a second control slot of a TDMA frame sequence.

16. A network device according to claim 13 wherein said link layer is configured to append control information related to transmission of a network joining message packet to a network joining message packet.

17. A network device according to claim 13 wherein said MAC layer is configured to subdivide the control slot of the TDMA frame sequence based on at least one of the size of the network joining packet and a data rate of a control slot queue to determine a number of network joining message packets that can be transmitted during the control slot.

18. A network device according to claim 13 wherein to set a line of sight azimuth, elevation, and transmission range for a field of regard for said antenna, said link layer is configured to:

set a lowest possible line of sight azimuth, elevation, and transmission range for a field of regard for said antenna for a first network joining message packet transmission.

19. A network device according to claim 13 wherein said antenna comprises a phased array antenna.

20. A network device according to claim 19 wherein said phased array antenna is configured to:

focus at the designated azimuth and elevation during a transmission control slot; and

defocus to emulate an omni-directional antenna for the field of regard extent of said phased array antenna during a receiving control slot.

21. A network device according to claim 13 whereupon transmission of a network joining message packet, said MAC layer is configured to send an interrupt to said link layer to cause said link layer to forward a next network joining message packet to said MAC layer along with its designated azimuth, elevation, and transmit range.

22. A network device according to claim 13 wherein said MAC layer is configured to place a network joining message packet into a next available control slot of a TDMA frame sequence that is configured as a transmit control slot.

23. A network device according to claim 13 wherein said processor is programmed to:

a) set a lowest possible line of sight azimuth, elevation, and transmission range for said transmitter and said antenna to be associated with a first network joining message packet transmission;

b) increment the line of sight azimuth by one 3 dB antenna beam width for subsequent network joining message packet transmissions until an extent for the line of sight azimuth is reached;

c) initiate routing protocol network communications in TDMA non-control data slots if a network response message is received;

d) reset the line of sight azimuth of said antenna to the lowest possible value;

e) incrementing the line of sight elevation by one 3 dB antenna beam width for subsequent network joining message packet transmissions;

f) repeat b) through e), until an extent for line of sight and elevation of said antenna is reached;

g) reset the line of sight azimuth and elevation for said antenna to the lowest possible settings;

h) increment the transmission range of said transmitter for subsequent network joining message packet transmissions;

i) repeat steps b) through h) until a maximum line of sight azimuth and a maximum elevation for said antenna, and a maximum transmission range for said transmitter is reached.

24. A network device according to claim 13 wherein to transmit multiple network joining message packets during a control slot of a time division multiple access (TDMA) frame sequence said link layer is configured to:

calculate a network joining message packet transmit time as the size of the network joining message packet divided by a transmission data rate; and

calculate a message travel time as a transmission range divided by the speed of light; and

cause a transmitting phased array antenna beam to point at an assigned azimuth and elevation for the duration of the combination of the packet transmit time and the message travel time.

25. A network device according to claim 13 wherein to transmit multiple network joining message packets during a control slot of a time division multiple access (TDMA) frame sequence, said link layer is configured to provide network joining message packets to said MAC layer until a guard time associated with the control slot occurs, the guard time fixed at a data communications maximum range for said network device divided by the speed of light.

26. A network device according to claim 25 wherein to calculate the number of network joining message packets that can be transmitted during a control slot, said link layer is configured to:

calculate a message packet transmit time as the size of the message packet divided by a transmission data rate;

calculate a message flight time as a transmission range divided by the speed of light; and

calculate the number of network joining message packets that can be transmitted during a control slot based on a duration of the control slot minus a guard time divided by the sum of packet transmit time and message flight time.

27. A network device according to claim 13 wherein said processor is configured to utilize the message routing protocol to initiate transmission of the network joining message packets.

28. A method for using the duration of a control slot of a time division multiple access (TDMA) frame sequence to transmit multiple network joining message packets from a network device, said method comprising:

determining a size of the network joining message packet to be transmitted by the network device;

calculating the number of network joining message packets that can be transmitted by the network device during a control slot based on the size of the network joining message packet and a transmission data rate associated with the TDMA frame sequence;

associating a specific line of sight azimuth, elevation, and range with each network joining message packet; and

transmitting, from the network device, a number of the network joining message packets during the control slot of the TDMA frame sequence, the number of network joining message packets transmitted based on the subdivision of the control slots.

29. A method according to claim 28 wherein calculating the number of network joining message packets that can be transmitted during a control slot comprises:

dividing the size of the network joining message packet by the transmission data rate; and

calculating a message packet travel time as a transmission range divided by the speed of light.

30. A method according to claim 29 further comprising calculating a total number of joining packets associated with the control slot such that the last network joining message packet transmitted during a control slot and the associated message travel time for the last message occur within the control slot time of the TDMA frame sequence minus a guard time for the control slot.

31. A method according to claim 28 further comprising randomly determining if the network joining message packets are to be transmitting during a first control slot or a second control slot of a TDMA frame sequence.