Broadband CDMA overlay system and method

• US 20010033562A1
• Filed: 06/11/2001
• Published: 10/25/2001
• Est. Priority Date: 12/05/1990
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Schilling, Donald L.
• Granted Patent: US 7,020,125 B2
• Time in Patent Office: Days
• US Class Current: 370/342
• CPC Class Codes: G01S 13/82 wherein continuous-type signals are transmitted
• CPC Class Codes: G01S 5/0036 of measured values, i.e. measurement on mobile and position calculation on base station
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: H04B 1/71 the interference being narrowband interference
• CPC Class Codes: H04B 1/7101 with estimation filters
• CPC Class Codes: H04B 1/7102 with transform to frequency domain
• CPC Class Codes: H04B 7/18547 for geolocalisation of a station position fixing by direction or distance determination G01S5/00
• CPC Class Codes: H04B 7/216 Code division or spread-spectrum multiple access [CDMA, SSMA]
• CPC Class Codes: H04B 7/2628 using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA] H04B7/2618 takes precedence
• CPC Class Codes: H04B 7/2631 for broadband transmission
• CPC Class Codes: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713
• CPC Class Codes: H04W 4/18 Information format or content conversion, e.g. adaptation by the network of the transmitted or received information for the purpose of wireless delivery to users or terminals
• CPC Class Codes: H04W 52/343 taking into account loading or congestion level
• CPC Class Codes: H04W 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A wireless communication system has spread spectrum and narrow band users. A selected base station produces a spread spectrum signal for transmission in a selected sector of the base station. The produced spread spectrum signal notch filters at frequencies. These frequencies are used by narrow band users located in the selected sector and sectors of base stations other than the selected base station adjacent tot he selected sector. The notch filtered signal is transmitted in the selected sector.

Claims

1. A method for non-interferingly transmitting spread spectrum signals in a wireless communication system, the wireless system having spread spectrum and narrow band uses, the method comprising:

from a selected base station, producing a spread spectrum signal for transmission in a selected sector of the base station;

notch filtering the produced spread spectrum signal at frequencies used by narrow band users located in the selected sector and sectors of base stations other than the selected base station being adjacent to the selected sector; and

transmitting the notch filtered signal in the selected sector.

2. The method of

claim 1

further comprising:

the selected base station transmitting a signal to a narrow band used in the selected sector using a frequency of the notched filtered frequencies of the produced spread spectrum signal.

3. The method of

claim 1

wherein the notch filtering is performed by a comb notch filter.

4. The method of

claim 3

wherein a controller controls frequencies notched by the comb notch filter.

5. The method of

claim 1

wherein the narrow band users are users of a time division multiple access system.

6. The method of

claim 1

wherein the narrow band users are users of a microwave system.