Method and apparatus for establishing spread spectrum communication

• US 5,455,822 A
• Filed: 12/03/1993
• Issued: 10/03/1995
• Est. Priority Date: 10/23/1990
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Omnipoint Corp. (Deutsche Telekom AG)
• Inventors: Dixon, Robert C., Vanderpool, Jeffrey S.
• Primary Examiner(s): Kizou, Hassan
• Application Number:
  US08/161,187
• Time in Patent Office: 669 Days
• Field of Search: 370/85.7, 370/95.1, 370/95.2, 370/95.3, 370/18, 370/85.8, 370/93, 375/1, 375/34, 375/58, 379/58, 379/59, 379/60, 379/61, 379/62, 379/63, 455/33, 455/53, 455/33.1, 455/33.4, 455/53.1, 455/54.2, 455/56.1, 380/44, 340/825.52
• US Class Current: 370/342
• CPC Class Codes: H04B 7/2628 using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA] H04B7/2618 takes precedence

Abstract

A method for establishing communications between a master unit and a plurality of node units. Of the plurality of node units, K node units are assumed to have established communications with a master unit. A first (K+1) node unit of the plurality of node units, desires to establish communications with the master unit. The method includes transmitting from the master unit, a base-station spread spectrum signal having a common signalling chip code, transmitting from the first node unit a second spread spectrum signal with a first identification code using the common-signalling chip code, transmitting from the master unit a third spread spectrum signal with a master unit identification code, using the common-signalling chip code. The method further includes generating at the first node unit using the master unit identification signal, a master unit chip code for transmitting spread spectrum signals to the master unit. Additionally, the method includes generating, at the master unit using the first identification code, a first node unit chip code for transmitting spread spectrum signals to the first node unit.

Claims

1. A method for establishing wireless communication using spread spectrum signals to communicate between a master unit and at least one remote unit, comprising the steps of:

transmitting a first master-initialization spread spectrum signal from said master unit in a first available time slot in a time frame, wherein said time frame is periodic and is comprised of a plurality of time slots and in which some of said time slots are available for communication and some of said time slots are unavailable for communication;

receiving said master-initialization spread spectrum signal at a first remote unit seeking to establish communication with said master unit in said first available time slot;

transmitting a first node-initialization spread spectrum signal from said first remote unit seeking to establish communication with said master unit in said first available time slot in response to receiving said master-initialization spread spectrum signal at said first remote unit;

receiving said first node-initialization spread spectrum signal at said master unit in said first available time slot;

transmitting a master-identification spread spectrum signal from said master unit, in said first available time slot in response to receiving said first node-initialization spread spectrum signal;

receiving said master-identification spread spectrum signal at said first remote unit seeking to establish communication with said master unit in said first available time slot;

transmitting a second node-initialization spread spectrum signal from said first remote unit seeking to establish communication with said master unit in response to receiving said master-identification spread spectrum signal;

receiving said second node-initialization spread spectrum signal at said master unit in said first available time slot;

transmitting a first communication spread spectrum signal from said master unit to said first remote unit seeking to establish communication with said master unit in said first available time slot;

receiving said first communication spread spectrum signal at said first remote unit seeking to establish communication with said master unit in said first available time slot;

transmitting a second communication spread spectrum signal from said first remote unit to said master unit in said first available time slot in response to receiving said first communication spread spectrum signal;

communicating between said master unit and said first remote unit in said first available time slot.

2. The method of claim 1 wherein said first master initialization spread spectrum signal is encoded using a first spectrum spreading code, said first spectrum spreading code resident in all of said remote units.

3. The method of claim 2 wherein said first spectrum spreading code is an M-ary code.

4. The method of claim 2 wherein said first node-initialization spread spectrum signal is encoded using said first spectrum spreading code, said first spectrum spreading code resident in said master unit.

5. The method of claim 2 wherein said first node-initialization spread spectrum signal comprises information data modulated by said first spectrum spreading code, said information data comprising information identifying said first remote unit.

6. The method of claim 2 wherein said first node-initialization spread spectrum signal comprises information data modulated by said first spectrum spreading code, said information data comprising an acknowledgment signal.

7. The method of claim 2 wherein said master identification spread spectrum signal comprises unique information for identifying said master unit modulated by said first spectrum spreading code.

8. The method of claim 7 further comprising the step of using said unique information for identifying said master unit contained in said master identification spread spectrum signal to select a third spectrum spreading code for communicating with said master unit.

9. The method of claim 8 wherein said third spectrum spreading code is an M-ary code.

10. The method of claim 2 wherein said second mode-initialization spread spectrum signal comprises unique information for identifying said first remote unit modulated by said first spectrum spreading code.

11. The method of claim 10 further comprising the step of using said unique information for identifying said first remote unit to select a fourth spectrum spreading code for communicating with said remote unit.

12. The method of claim 11 wherein said fourth spectrum spreading code is an M-ary code.

13. The method of claim 1 wherein said first master initialization spread spectrum signal comprises information data comprising indexing and addressing information for said first available time slot.

14. The method of claim 1 wherein said first node-initialization spread spectrum signal is encoded using a second spectrum spreading code, said second spectrum spreading code resident in said master unit.

15. The method of claim 14 wherein said second spreading code is an M-ary code.

16. The method of claim 14 wherein said first node-initialization spread spectrum signal comprises information data modulated by said second spectrum spreading code, said information data comprising information identifying said first remote unit.

17. The method of claim 14 wherein said first node-initialization spread spectrum signal comprises information data contained in said master-initialization spread spectrum signal received from said master unit, said information data comprising an acknowledgment signal.

18. The method of claim 14 wherein said master identification spread spectrum signal comprises unique information for identifying said master unit modulated by said second spectrum spreading code.

19. The method of claim 18 further comprising the step of using said unique information for identifying said master unit contained in said master identification spread spectrum signal to select a third spectrum spreading code for communicating with said master unit.

20. The method of claim 19 wherein said third spectrum spreading code is an M-ary code.

21. The method of claim 11 wherein said second node-initialization spread spectrum signal comprises unique information for identifying said first remote unit modulated by said first spectrum spreading code.

22. The method of claim 21 further comprising the step of using said unique information for identifying said first unit to select a fourth spectrum spreading code for communicating with said node unit.

23. The method of claim 22 wherein said fourth spectrum spreading code is an M-ary code.

24. The method of claim 1 wherein said master identification spread spectrum signal comprises unique information for identifying said master unit.

25. A method for establishing communications between a master unit a node unit by using time division multiple access, wherein a plurality of time slots comprise a time frame, comprising the steps of:

transmitting from said master unit an initialization signal in a time slot in a first time frame;

transmitting in said same time slot in said first time frame from a node unit desiring to establish communication with said master unit, responsive to receiving said initialization signal at said node unit, an initialization acknowledgment signal identifying said node unit,

transmitting in said same time slot in a second time frame from said master unit, responsive to receiving said initialization acknowledgment signal at said master unit, an identification signal identifying a slot position comprising one or more available vacant time slots, and

communicating from said master unit to said node unit within said slot position using a first spread spectrum code, and communicating from said node unit to said master unit within said slot position using a second spread spectrum code.

26. The method of claim 25 wherein at least one of said initialization signal, said initialization acknowledgment signal, and said identification signal comprises a spread spectrum signal.

27. The method of claim 25 wherein said first spread spectrum code is an M-ary code.

28. The method of claim 25 wherein said second spread spectrum code is an M-ary code.

29. A method for establishing communications between a master unit and a node unit by using time division multiple access, wherein a plurality of time slots comprise a time frame, comprising the steps of:

transmitting from said master unit an initialization signal in an original time slot in a first time frame,

transmitting in said original time slot in said first time frame from a node unit desiring to establish communication with the master unit, responsive to receiving said initialization signal at said node unit, an initialization acknowledgment signal identifying said node unit,

transmitting in an available time slot in said first time frame different from said original time slot from said master unit, responsive to receiving said initialization acknowledgment signal at said master unit, a master identification signal, and

communicating from said master unit to said node unit and said node unit to said master unit in said available time slot using a first spread spectrum code.

30. A method for establishing communications between a master unit and a node unit by using time division multiple access, wherein a plurality of time slots comprise a time frame, comprising the steps

transmitting from said master unit an initialization signal in an unused time slot,

transmitting in said unused time slot from a node unit desiring to establish communication with the master unit, responsive to receiving said initialization signal at said node unit, an initialization acknowledgment signal identifying said node unit,

transmitting from said master unit, responsive to receiving said initialization acknowledgment signal at said master unit, a master identification signal identifying said master unit, and

communicating from said master unit to said node unit using a spread spectrum signal including address bits for accessing said node unit, said node unit having a unique address corresponding to said address bits, and communicating from said node unit to said master unit using a spread spectrum code selected based on the identity of said master unit.

31. The method of claim 30 wherein at least one of said initialization signal, said initialization acknowledgment signal, and said master identification signal comprises a spread spectrum signal.

32. A method for communicating between a master unit and a plurality of node units using time division multiple access, comprising the steps of:

transmitting form said master unit, using a first selected time slot and a first spread spectrum signal, an initialization signal,

transmitting from a first node seeking to communicate with said master unit, using said first selected time slot, an initialization acknowledgment signal in response to said initialization signal,

transmitting from said master unit using said first selected time slot an identification signal comprising a master unit identifier,

transmitting from said first node unit, in response to said identification signal, using said first selected time slot an identification acknowledgment signal comprising a node unit identifier, and

communicating from said master unit to said first node unit using a spread spectrum code selected based upon said node unit identifier, and communicating from said first node unit to said master unit using said first selected time slot and a spread spectrum code selected based upon said master unit identifier.

33. The method of claim 32 wherein at least one of said initialization signal, said initialization acknowledgment signal, said identification signal, and said identification acknowledgment signal comprises a spread spectrum signal.

34. A method for establishing communications between a master unit and a node unit by using time division multiple access comprising:

transmitting from said master unit an initialization signal,

in response to said initialization signal, transmitting from a node unit desiring to establish communication with the master unit an initialization acknowledgment signal identifying said node unit, said initialization acknowledgment signal being transmitted in a designated time slot,

in response to said initialization acknowledgment signal, transmitting from said master unit a master identification signal identifying said master unit in said designated time slot, and

communicating from said node unit to said master unit in said designated time slot using an M-ary spread spectrum code.

35. The method of claim 34 further comprising the step of communicating from said master unit to said node unit using a second M-ary spread spectrum code.

36. The method of claim 35 wherein said second spread spectrum code is selected based upon the identity of said master unit.

37. The method of claim 35 wherein said second spread spectrum code is common to a plurality of node units accessible to said master unit.