Wireless communications protocol

• US 6,169,730 B1
• Filed: 05/15/1998
• Issued: 01/02/2001
• Est. Priority Date: 05/15/1998
• Status: Expired due to Term

• Current Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Original Assignee: Northrop Grumman Corporation
• Inventors: Stratmoen, Scott Alan, Jacklin, William Edward
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Pizarro, Ricardo M.
• Application Number:
  US09/079,651
• Time in Patent Office: 963 Days
• Field of Search: 370/337, 370/345, 370/347, 370/310, 370/315, 370/313, 370/321, 370/458, 370/465, 370/468, 370/348, 455/422, 455/435, 455/437
• US Class Current: 370/321
• CPC Class Codes: H04B 7/2656 for structure of frame, burst

Abstract

A method for implementing a time division multiple access protocol for digital communications between a radio transceiver and a repeater or another radio transceiver has the steps of dividing a radio communication into a plurality of frames having a predetermined length of time; dividing each frame into: a plurality of downlink slots, each downlink slot containing a transmission from the repeater to the transceiver; and a plurality of uplink slots, each uplink slot containing a transmission from the transceiver to the repeater.

Claims

1. A method for implementing a time division multiple access protocol for digital communications between a radio transceiver and a repeater, the method comprising the steps of:

a) dividing a communication into a plurality of frames having a predetermined length of time;

b) dividing each frame into;

i) a plurality of downlink slots, each downlink slot for containing a transmission from the repeater to the transceiver;

ii) a plurality of uplink slots, each uplink slot for containing a transmission from the transceiver to the repeater;

iii) wherein each of the downlink and uplink slots are divided into;

(a) a bit synchronization for timing acquisition field;

(b) a slot field for slot acquisition;

(c) a header field for control information, wherein the header field is further divided into;

(i) a message type field for identifying a message type;

(ii) a message subtype field for identifying a point-to-point mode of communication;

(iii) an user-programmable ID field for identifying sending/receiving transceivers;

(iv) a reserved field for providing subsequent additional protocol information;

(v) a first modifier field for identifying communication channels;

(vi) a second modifier field for identifying available uplink slots and current active slots;

(d) a data field for digital audio and digital data information;

(e) a 16-bit CRC field for error detection;

(f) a slot gap field for accommodating clock inaccuracies; and

c) transmitting the communication.

2. The method as recited in claim 1, wherein the step of dividing the communication into the plurality of frames comprises dividing the voice communication into a plurality of frames.

3. The method as recited in claim 1, wherein the step of dividing the communication into the plurality of frames comprises dividing the data communication into a plurality of frames.

4. The method as recited in claim 1, wherein the step of dividing the communication into the plurality of frames comprises dividing the communication into the plurality of frames, each frame having a length of approximately 5.12 milliseconds.

5. The method as recited in claim 1, wherein the steps of dividing each if the frames into the plurality of downlink slots and the plurality of uplink slots comprises dividing each frame into a plurality of paired downlink and uplink slots having corresponding indices.

6. The method as recited in claim 1, further comprising the step of using a Medium Access Control (MAC) algorithm to access available uplink slots.

7. The method as recited in claim 1, further comprising the steps of:

a) a radio transceiver accessing an available uplink slot to transmit information to the repeater; and

b) the repeater using a corresponding downlink slot to transmit information to the radio transceiver.

8. The method as recited in claim 1, further comprising the step of:

a) defining a downlink slot D₀;

b) the repeater transmitting information to radio transceivers that do not have an uplink slot via downlink slot D₀.

9. The method as recited in claim 1, further comprising the step of defining a frame gap intermediate adjacent frames to prevent adjacent frames from overlapping due to clock inaccuracies.

10. The method as recited in claim 1, further comprising the step of defining a frame gap intermediate adjacent frames to facilitate synthesizer re-programming in a frequency hopping spread spectrum system.

11. The method as recited in claim 1, wherein the step of dividing each downlink slot and each uplink slot into a header field comprises dividing each downlink slot and each uplink slot into a header field comprising:

a) a message type field;

b) a message subtype field;

c) an ID field;

d) a reserved field;

e) a first modifier field; and

f) a second modifier field.

12. The method as recited in claim 11, wherein the step of dividing each downlink slot and each uplink slot into the ID field comprises dividing each of the downlink slots and each of the uplink slots into the ID field that facilitates transceiver to transceiver communications.

13. The method as recited in claim 11 wherein the step of dividing each of the downlink slots and each of the uplink slots into the message type field comprises dividing each of the downlink slots and each of the uplink slots into an 8-bit message type field so as to facilitate an identification of 256 different message types.

14. A method for implementing a time division multiple access protocol for digital communications between a radio transceiver and a repeater, the method comprising the steps of:

a) dividing a communication into a plurality of frames having a predetermined length of time;

b) dividing each frame into;

i) a plurality of downlink slots, each downlink slot for containing a transmission from the repeater to the transceiver;

ii) a plurality of uplink slots, each uplink slot for containing a transmission form the transceiver to the repeater;

iii) wherein each of the downlink and uplink slots are divided into;

(a) a bit synchronization for timing acquisition field;

(b) a slot field for slot acquisition;

(c) a header field for control information, wherein the header field is further divided into;

(i) a message type field for identifying a message type;

(ii) a message subtype field for identifying a point-to-point mode of communications;

(iii) an user programmable ID field for identifying sending/receiving transceivers;

(iv) a reserved field for providing subsequent additional protocol information;

(v) a first modifier field for identifying communication channels;

(vi) a second modifier field for identifying available uplink slots and current active slots;

(d) a data field for digital audio and digital data information;

(e) a CRC field for error detection;

(f) a slot gap field for accommodating clock inaccuracies; and

c) transmitting the communication.

15. The method of claim 14 wherein step a) comprises dividing a voice communication into the plurality of frames.

16. The method of claim 14 wherein step a) comprises dividing a data communication into the plurality of frames.

17. The method of claim 14 wherein step a) comprises dividing the communication into the plurality of frames each having a length of approximately 5.12 milliseconds.

18. The method of claim 14 wherein step b) comprises dividing each of the frames into the plurality of paired downlink and uplink slots having corresponding indices.

19. The method of claim 14 wherein step b) further comprises utilizing a Medium Access Control (MAC) algorithm to access available uplink slots.

20. The method of claim 14 wherein step b) further comprises:

a) defining a downlink slot D₀; and

b) the repeater transmitting information via the downlink slot D₀ to radio transceivers without the uplink slots.

21. The method of claim 14 wherein step b) further comprises forming a frame gap intermediate adjacent frames to prevent adjacent frames from overlapping due to clock inaccuracies.

22. The method of claim 14 wherein step b) further comprises forming a frame gap intermediate adjacent frames to facilitate synthesizer re-programming in a frequency hopping spread spectrum system.

23. The method of claim 14 wherein step b)iii)(5) further comprises dividing each of the downlink and uplink slots into a 16-bit CRC field for error detection.

24. The method of claim 14 wherein step b)iii)(3)(c) further comprises dividing each of the downlink and uplink slots into the ID field that facilitates transceiver to transceiver communications.

25. The method of claim 14 wherein step b)iii)(3)(a) further comprises dividing each of the downlink and uplink slots into an 8-bit message type field to facilitate an identification of 256 different message types.

26. The method of claim 14 wherein step c) further comprises:

a) the radio transceiver transmitting information via an available uplink slot to the repeater; and

b) the repeater transmitting information via a corresponding downlink slot to the radio transceiver.

27. A method for implementing a time division multiple access protocol for communication between a repeater and at least one radio transceiver, the method comprising the steps of:

a) segmenting a voice communication into a plurality of frames having a predetermined length of time;

b) segmenting each frame into a plurality of downlink and uplink slots, each downlink slot having transmissions from the repeater to the transceiver(s) therein, each uplink slot having transmissions from the receiver(s) to the repeater therein;

c) wherein each of the downlink and uplink slots are divided into;

i) a bit synchronization for timing acquisition field;

ii) a slot field for slot acquisition;

iii) a header field for control information, wherein the header field is further divided into;

(a) a message type field for identifying a message type;

(b) a message subtype field for identifying a point-to-point mode of communications;

(c) an user-programmable ID field for identifying sending/receiving transceivers;

(d) a reserved field for providing subsequent additional protocol information;

(e) a first modifier field for identifying communication channels;

(f) a second modifier field for identifying available uplink slots and current active slots;

iv) a data field for digital audio and digital data information;

v) a 16-bit CRC field for error detection;

vi) a slot gap field for accommodating clock inaccuracies;

d) transmitting the voice communication.

28. The method of claim 27 wherein step a) comprises segmenting a digital communication into the plurality of frames.

29. The method of claim 27 wherein step a) comprises segmenting a data communication into the plurality of frames.

30. The method of claim 27 wherein step a) comprises segmenting the communication into the plurality of frames each having a length of approximately 5.12 milliseconds.

31. The method of claim 27 wherein step b) comprises segmenting each of the frames into the plurality of paired downlink and uplink slots having corresponding indices.

32. The method of claim 27 wherein step b) further comprises utilizing a Medium Access Control (MAC) algorithm to access available uplink slots.

33. The method of claim 27 wherein step b) further comprises:

a) defining a downlink slot D₀; and

b) the repeater transmitting information via the downlink slot D₀ to radio transceivers without the uplink slots.

34. The method of claim 27 wherein step b) further comprises forming a frame gap intermediate adjacent frames to prevent adjacent frames from overlapping due to clock inaccuracies.

35. The method of claim 27 wherein step b) further comprises forming a frame gap intermediate adjacent frames to facilitate synthesizer reprogramming in a frequency hopping spread spectrum system.

36. The method of claim 27 wherein step b) further comprises segmenting each of the downlink and uplink slots into:

a) a bit synchronization for timing acquisition field;

b) a slot field for slot acquisition;

c) a header field for control information;

d) a data field for digital audio and digital data information;

e) a CRC field for error detection; and

f) a slot gap field for accommodating clock inaccuracies.

37. The method of claim 36 wherein step c) further comprises segmenting the header field into:

a) a message type field;

b) a message subtype field;

c) an ID field;

d) a reserved field;

e) a first modifier field; and

f) a second modifier field.

38. The method of claim 37 wherein step a) further comprises segmenting each of the downlink and uplink slots into an 8-bit message type field to facilitate identification of 256 different message types.

39. The method of claim 36 wherein step e) further comprises segmenting each of the downlink and uplink slots into a 16-bit CRC field.

40. The method of claim 27 wherein step c) further comprises:

a) the radio transceiver(s) transmitting information via an available uplink slot to the repeater; and

b) the repeater transmitting information via a corresponding downlink slot to the radio transceiver(s).