Spread spectrum communication system

• US 6,229,792 B1
• Filed: 06/07/1995
• Issued: 05/08/2001
• Est. Priority Date: 11/01/1993
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Xircom Incorporated (Intel Corporation)
• Inventors: Peterson, Peter O., Dixon, Robert C., Smith, Douglas G., Anderson, Gary B.
• Primary Examiner(s): VU, HUY DUY
• Application Number:
  US08/485,774
• Time in Patent Office: 2,162 Days
• Field of Search: 370/95.1, 370/95.3, 370/110.1, 370/60, 370/60.1, 370/56, 370/18, 370/276, 370/279, 370/280, 370/281, 370/294, 370/295, 370/310, 370/314, 370/319, 370/320, 370/321 , 370/328, 370/335, 370/336, 370/337, 370/338, 370/342, 370/343, 370/345, 370/401, 370/420, 370/352, 370/466, 370/467, 370/522, 375/201, 375/202, 375/205, 375/206, 379/58, 379/59, 379/60, 379/63, 379/229, 379/225, 379/231, 379/232, 379/234, 379/219, 455/33.1, 455/33.4, 455/34.1, 455/51.1, 455/51.2, 455/53.1, 455/56.1
• US Class Current: 370/280
• CPC Class Codes: G10L 19/012 Comfort noise or silence coding
• CPC Class Codes: H04B 7/0805 with single receiver and antenna switching H04B7/0822 takes precedence
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity
• CPC Class Codes: H04B 7/2618 using hybrid code-time division multiple access [CDMA-TDMA]
• CPC Class Codes: H04B 7/2643 using time-division multiple access [TDMA] H04B7/2615, H04B7/2618 take precedence
• CPC Class Codes: H04B 7/2668 Arrangements for Wireless Code-Division Multiple Access [CDMA] System Synchronisation, for code acquisition H04B1/7075, for code tracking H04B1/7085
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 47/50 Queue scheduling
• CPC Class Codes: H04L 47/522 Dynamic queue service slot or variable bandwidth allocation
• CPC Class Codes: H04L 47/6215 Individual queue per QOS, rate or priority
• CPC Class Codes: H04L 49/90 Buffering arrangements
• CPC Class Codes: H04L 49/901 using storage descriptor, e.g. read or write pointers
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 36/0058 Transmission of hand-off measurement information, e.g. measurement reports
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 36/30 by measured or perceived connection quality data
• CPC Class Codes: H04W 36/36 by user or terminal equipment
• CPC Class Codes: H04W 52/04 TPC
• CPC Class Codes: H04W 52/08 : Closed loop power control
• CPC Class Codes: H04W 52/24 : using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 52/36 : with a discrete range or set of values, e.g. step size, ramping or offsets
• CPC Class Codes: H04W 52/362 : Aspects of the step size
• CPC Class Codes: H04W 52/367 : Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 52/38 : TPC being performed in particular situations
• CPC Class Codes: H04W 52/40 : during macro-diversity or soft handoff
• CPC Class Codes: H04W 56/00 : Synchronisation arrangements
• CPC Class Codes: H04W 72/044 : based on the type of the allocated resource
• CPC Class Codes: H04W 72/0446 : Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/20 : Control channels or signalling for resource management
• CPC Class Codes: H04W 74/06 : using polling
• CPC Class Codes: H04W 76/10 : Connection setup
• CPC Class Codes: H04W 8/04 : Registration at HLR or HSS [Home Subscriber Server]
• CPC Class Codes: H04W 92/12 : between access points and access point controllers

Abstract

A simple and flexible over-air protocol for use with a mobile telephone system, having hand-held telephones in a microcell or other type of cellular communication system. A method in which user stations communicate with one or more base stations to place and receive telephone calls, in which the user stations are provided a secure voice or data link and have the ability to handoff calls between base stations while such calls are in progress. Each base station has a set of “air channels” to which it transmits in sequence. The air channels supported by each base station are called that base station'"'"'s “polling loop”. A user station receives general polling information on an unoccupied air channel, transmits responsive information to the base station, and awaits acknowledgment from the base station. Each base station may therefore simultaneously maintain communication with as many user stations as there are air channels in its polling loop. The ability of a user station to communicate on any unoccupied air channel makes the protocol air-channel agile, while the stability of user station and base station clocks may define air channels, gaps, and minor frames.

Claims

1. wireless communication system comprising:

a plurality of cells each defined by a combination of a spread spectrum code group selected from a plurality of spread spectrum code groups and a frequency group selected from a plurality of frequency groups, said plurality of cells being arranged in a repeating pattern according to said combination;

a plurality of base stations located in said plurality of cells;

a base station controller coupled to a first cluster of base stations of said plurality of base stations, said base station controller being operatively connectable to a GSM network for carrying all traffic between said first cluster of base stations and the GSM network and operatively connectable directly to a switch of an AIN-based network for carrying all traffic between said first cluster of base stations and the AIN-based network without connecting through a mobile switching center; and

a user station communicating with said first cluster of base stations using a spread spectrum communication technique in time division duplex communication, said user station measuring qualities of a plurality of air channels between said user station and said first cluster of base stations and performing data transfer between said user station and said first cluster of base stations over a selected air channel in response to a superior quality of the selected air channel.

2. The wireless communication system of claim 1 wherein said base station controller comprises a local cache database.

3. The wireless communication system of claim 1 wherein said base station controller manages local registration and verification of said first cluster of base stations.

4. The wireless communication system of claim 1 wherein said base station controller assists in handoffs of said user station between said first cluster of base stations by directing data to a base station of said first cluster of base stations having the selected air channel of the superior quality in response to a request from said user station.

5. The wireless communication system of claim 1 further comprising a second base station controller coupled to a second cluster of base stations of said plurality of base stations, said second base station controller being operatively connectable to the GSM network for carrying all traffic between said second cluster of base stations and the GSM network and operatively connectable directly to the switch of the AIN-based network for carrying all traffic between said second cluster of base stations and the AIN-based network without connecting through a mobile switching center, wherein said user station further measures qualities of a plurality of air channels between said user station and said second cluster of base stations.

6. The wireless communication system of claim 1 wherein said base station controller is further operatively connectable to a cable distribution network for carrying all traffic between said first cluster of base stations and the cable distribution network without connecting through a mobile switching center.

7. The wireless communication system of claim 1 wherein said base station controller comprises a receiver for receiving an external timing marker by which the timing of said first cluster of base stations is synchronized.

8. The wireless communication system of claim 5 wherein said base station controller and said second base station controller redirect data from a base station of said first cluster of base stations to a base station of said second cluster of base stations having the selected air channel of the superior quality in response to a request from said user station.

16. The wireless communication system of claim 1 wherein said base station controller is connected directly to said AIN-based network without connecting through a mobile switching center.

17. The wireless communication system of claim 1 wherein said selected base station of said first cluster of base stations communicates with said user station using the same over-the-air protocol regardless of whether said base station controller is operatively connected to the GSM network or to the AIN-based network.

9. A wireless communication system comprising:

a user station;

a plurality of base stations, each capable of communicating with said user station by using a spread spectrum communication technique in a time division duplex communication;

a plurality of cells each containing at least one of said plurality of base stations and defined by a combination of a spread spectrum code group selected from a plurality of spread spectrum code groups and a frequency group selected from a plurality of frequency groups, said plurality of cells being arranged in a repeating pattern according to said combination;

a base station controller coupled to a first one and a second one of said plurality of base stations and having a first configuration whereby said base station controller is operatively connectable to a GSM network through a mobile switching center for carrying all traffic between said first and second base stations and the GSM network, and a second configuration whereby said base station controller is operatively connectable directly to a switch of an AIN-based network for carrying all traffic between said first and second base stations and the AIN-based network without connecting through a mobile switching center; and

wherein said user station measures qualities of a plurality of air channels between said user station and said first and second base stations and performs data transfer between said user station and said first and second base stations over a selected air channel in response to a superior quality of the selected air channel.

10. The wireless communication system of claim 9 wherein:

a first cell of said plurality of cells shares the same code group as two adjacent cells; and

a frequency group of said first cell differs front a frequency group of each of its adjacent cells.

11. The wireless communication system of claim 9 wherein said plurality of frequency groups comprises a first frequency group, a second frequency group, and a third frequency group, no cell of a given frequency group being adjacent to another cell of the same frequency group.

12. The wireless communication system of claim 9 wherein said user station may be handed off between said first base station and said second base station with the assistance of said base station controller, said base station controller directing data to one of said first and second base stations in response to a request from the user station.

13. The wireless communication system of claim 12 further comprising a second base station controller coupled to a third base station of said plurality of base stations, wherein said user station may be handed off between said first base station and said third base station.

14. The wireless communication system of claim 9 wherein said base station controller comprises a receiver for receiving an external timing marker by which the timing of said base stations are synchronized.

15. The wireless communication system of claim 14 wherein said receiver comprises a GPS receiver.

18. The wireless communication system of claim 9 wherein the AIN-based network utilizes an ISDN protocol.

19. The wireless communication system of claim 9 wherein said base station controller is operatively connectable to the switch of the AIN-based network through a Bellcore Generic C interface.

20. The wireless communication system of claim 9 wherein said first base station communicates with said user station using the same over-the-air protocol regardless of whether said base station controller is operatively connected to the GSM network or the AIN-based network.

21. A wireless communication system comprising:

a plurality of cells each defined by a combination of selectable spread spectrum codes and operating frequencies;

a plurality of base stations located in said plurality of cells;

a first base station controller coupled to a first cluster of base stations of said plurality of base stations, said first base station controller being operatively connectable to a first network through a mobile switching center for carrying all traffic between said first cluster of base stations and said first network and operatively connectable directly to a switch of a second network for carrying all traffic between said first cluster of base stations and said second network, without connecting through a mobile switching center;

a second base station controller coupled to a second cluster of base stations of said plurality of base stations, said second base station controller being operatively connectable to the first network through the mobile switching center for carrying all traffic between said second cluster of base stations and said first network and operatively connectable directly to the switch of the second network for carrying all traffic between said second cluster of base stations and said second network, without connecting through a mobile switching center; and

a user station capable of communicating with said first and second clusters of base stations using a spread spectrum communication technique in time division duplex communication, said user station measuring qualities of a plurality of air channels between said user station and said first and second clusters of base stations and performing data transfer between said user station and a selected base station of said first and second clusters of base stations over a selected air channel in response to a superior quality of the selected air channel.

22. The wireless communication system of claim 21 wherein said user station communicates with said first and second clusters of base stations in time division duplex.

23. The wireless communication system of claim 21 wherein said user station communicates with said first and second clusters of base stations in frequency division duplex.

24. The wireless communication system of claim 21 wherein at least one of said first network and said second network comprises a personal communication system.

25. The wireless communication system of claim 21 wherein at least one of said first network and said second network comprises any one of a private branch exchange (PBX) system, a Centrex system, and a KTS system.

26. The wireless communication system of claim 21 wherein said selected base station communicates with said user station using the same over-the-air protocol regardless of whether said first and base station controllers are operatively connected to said first network or said second network.

27. A wireless communication system comprising:

a plurality of user stations;

a plurality of base stations, each capable of communicating with said plurality of user stations by transmitting and receiving spread spectrum signals;

a plurality of cells each containing at least one of said plurality of base stations;

a base station controller coupled to a cluster of base stations of said plurality of base stations and having a first configuration whereby said base station controller is operatively connectable to a first network through a mobile switching center for carrying all traffic between said cluster of base stations and said first network, a second configuration whereby said base station controller is operatively connectable directly to a switch of a second network for carrying all traffic between said cluster of base stations and said second network, and a third configuration wherein said base station controller is operatively connectable to a third network for carrying all traffic between said cluster of base stations and said third network;

wherein at least one of said first, second, and third networks comprises a personal communication network, at least one of said first, second, and third networks comprises a public switched telephone network, and said base station controller is operatively connectable to at least one of said second and third networks without connecting through a mobile switching center; and

wherein a user station of said plurality of user stations measures qualities of a plurality of air channels between said user station and said cluster of base stations and performs data transfer between said user station and a selected base station of said cluster of base stations over a selected air channel in response to a superior quality of the selected air channel.

28. The wireless communication system of claim 27 wherein said cluster of base stations communicate with said plurality of user stations using a time division duplex technique.

29. The wireless communication system of claim 27 wherein said cluster of base stations communicate with said plurality of user stations using a frequency division duplex technique.

30. The wireless communication system of claim 27 wherein at least one of said cluster of base stations communicates with at least one of said plurality of user stations using the same over-the-air protocol regardless of whether said base station controller is operatively connected to said first network, said second network, or said third network.