Dynamic capacity allocation CDMA spread spectrum communications

• US 5,367,533 A
• Filed: 06/07/1993
• Issued: 11/22/1994
• Est. Priority Date: 12/05/1990
• Status: Expired due to Term

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Schilling, Donald L.
• Primary Examiner(s): CANGIALOSI, SALVATORE A
• Application Number:
  US08/072,783
• Time in Patent Office: 533 Days
• Field of Search: 375/1, 380/34
• 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 1/7102 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: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713
• CPC Class Codes: H04J 13/0077 Multicode, e.g. multiple codes assigned to one user
• CPC Class Codes: H04L 5/02 Channels characterised by the type of signal
• 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 72/542 using measured or perceived quality
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A dynamic capacity allocation spread spectrum CDMA communications system for overlaying, at least in part, geographically and in frequency a radio-relay system. A first receiver, located near the relay receiver of the radio-relay system, measures a first power level within the relay bandwidth of the radio-relay system. A second receiver, located near the relay receiver, measures a second power level outside the relay bandwidth of the radio-relay system. The first power level is compared to a predetermined threshold. A ratio signal is generated from the first power level and the second power level. When the first power level exceeds the predetermined threshold, the ratio signal is used to regulate the power level and dynamically allocate the capacity transmitted from each spread-spectrum-base station.

Claims

1. A system for dynamically allocating power and capacity of a spread spectrum system having at least one spread-spectrum-base station, with said spread spectrum system overlaying, at least in part, in frequency and in a same geographical area as a radio-relay system, said radio relay system having at least one relay station with the geographical area, said radio-relay system having a signal with a radio-relay bandwidth, comprising:

a first receiver, located near a relay receiver of said radio-relay system, for measuring with a bandwidth approximately equal to the radio-relay bandwidth for transmitting the signal to said radio-relay system, a first power level within the radio-relay bandwidth of said radio-relay system;

a second receiver, located near said relay receiver of said radio-relay system, for measuring with a bandwidth approximately equal the radio-relay bandwidth for transmitting the signal to said radio-relay system, a second power level outside the radio-relay bandwidth of said radio-relay system;

means, located at each relay station, for coupling the signal received at said relay station to at said first receiver and to said second receiver;

means for comparing the first power level to a predetermined threshold;

means for generating a ratio signal from the first power level and the second power level; and

first means for regulating, when the first power level exceeds the predetermined threshold, a power level transmitted from the spread-spectrum-base station located within the geographical region in response to the ratio signal; and

second means for regulating, when the first power level exceeds the predetermined threshold, a number of user units accessing the spread-spectrum-base station.

2. The system as set forth in claim 1 wherein said coupling means includes a diplexer for coupling the signal received at said relay station to said first receiver and to said second receiver.

3. The system as set forth in claim 2 wherein:

said first receiver includes a first bandpass filter with a first bandwidth approximately equal to the radio-relay bandwidth and with the first bandwidth overlapping the radio-relay bandwidth; and

said second receiver includes a second bandpass filter with a second bandwidth approximately equal to the radio-relay bandwidth and with the second bandwidth located near in frequency and not overlapping the radio-relay bandwidth.

4. The system as set forth in claim 3 wherein:

said first reciever further includes a first detector, coupled to said first bandpass filter, for detecting the first power level within the radio-relay bandwidth; and

said second receiver further includes a second detector, coupled to said second bandpass filter, for detecting the second power level outside the radio-relay bandwidth.

5. The system as set forth in claim 4, further comprising:

a multiplexer, coupled to the first detector and the second detector, for multiplexing the detected first power level and the detected second power level;

an analog-to-digital converter for digitizing the detected first power level and the detected second power level; and

wherein said comparing means and said generating means include a processor for comparing the first power level to the predetermined threshold and for generating the ratio signal from the first power level and the second power level.

6. The system as set forth in claim 5 wherein said first regulating means includes a variable gain device, responsive to the ratio signal, for adjusting a power level transmitted from the spread-spectrum-base station.

7. The system as set forth in claim 5 wherein said second regulating means includes a controller, located at the spread-spectrum-base station, the controller responsive to the ratio signal for sending a message signal to a plurality of spread-spectrum users communicating with the spread-spectrum-base station, indicating when the spread-spectrum-base station is in a power-down mode.

8. The system as set forth in claim 4 further comprising:

a first analog-to-digital converter for digitizing the first power level;

a second analog-to-digital converter for digitizing the second power level; and

wherein said comparing means and second generating means include a processor for comparing the first power level to the predetermined threshold and for generating the ratio signal from the first power level and the second power level.

9. The system as set forth in claim 8 wherein said first regulating means includes a variable gain device, responsive to the ratio signal, for adjusting a power level transmitted from the spread-spectrum-base station.

10. The system as set forth in claim 8 wherein said second regulating means includes a controller, located at the spread-spectrum-base station, the controller responsive to the ratio signal for sending a message signal to a plurality of spread-spectrum users communicating with the spread-spectrum-base station, indicating when the spread-spectrum-base station is in a power-down mode.

11. The system as set forth in claim 2 wherein said first regulating means includes a variable gain device, responsive to the ratio signal, for adjusting a power level transmitted from the spread-spectrum-base station.

12. The system as set forth in claim 2 wherein said second regulating means includes a controller, located at spread-spectrum-base station, the controller responsive to the ratio signal for sending a message signal to a plurality of spread-spectrum users communicating with the spread-spectrum-base station, indicating when the spread-spectrum-base station is in a power-down mode.

13. A system for dynamically allocating power and capacity of a spread spectrum system having at least one spread-spectrum-base station, with said spread spectrum system overlaying, at least in part, in frequency and in a same geographical area as a radio-relay system, said radio-relay system having a signal with a radio-relay bandwidth, comprising:

a first receiver for measuring a first power level within the radio-relay bandwidth of said radio-relay system;

a second receiver for measuring a second power level within the radio-relay bandwidth of said radio-relay system;

means for comparing the first power level to predetermined threshold;

means for generating a ratio signal from the first power level and the second power level; and

means for regulating, when the first power level exceeds the predetermined threshold, a power level transmitted from the spread-spectrum-base station in response to the ratio signal.

14. A system for dynamically allocating power and capacity of a spread spectrum system having at least one spread-spectrum-base station, with said spread spectrum system overlaying, at least in part, in frequency and in a same geographical area as a radio-relay system, said radio-relay system having a signal with a radio-relay bandwidth, comprising:

a first receiver for measuring a first power level within the radio-relay bandwidth of said radio-relay system;

a second receiver for measuring a second power level outside the radio-relay bandwidth of said radio-relay system;

means for comparing the first power level to predetermined threshold;

means for generating a ratio signal from the first power level and the second power level; and

means for regulating, when the first power level exceeds the predetermined threshold, a number of user units accessing the spread-spectrum-base station.