Overlaying spread-spectrum satellite system and method

• US 5,469,468 A
• Filed: 09/27/1993
• Issued: 11/21/1995
• 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): GREGORY, BERNARR E
• Application Number:
  US08/127,261
• Time in Patent Office: 785 Days
• Field of Search: 380/34, 375/1, 455/12.1, 455/33.1, 379/59
• US Class Current: 375/130
• 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: 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 16/02 Resource partitioning among network components, e.g. reuse partitioning
• 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

Abstract

A spread-spectrum satellite system for communicating data and paging messages to a plurality of remote units. The spread-spectrum communications system has a satellite with an antenna beamwidth located within a same geographical region as covered by an existing FDMA, TDMA or other mobile-satellite system. The spread-spectrum satellite system has a device for converting the format of the data into a form suitable for communicating over radio waves, a spread-spectrum modulator for spread-spectrum processing the data, and a transmitter for transmitting the spread-spectrum-processed-converted data from the satellite to a remote unit. The remote unit has an antenna and a spread-spectrum receiver for recovering data communicated from the satellite. The remote unit optionally may have a comb filter for notch filtering mobile channels of the mobile-satellite system.

Claims

1. A spread-spectrum satellite system for communicating data from a satellite to a plurality of remote pager units, said spread-spectrum satellite system having said plurality of remote pager units located in a same geographical region as covered by a mobile-satellite system, with the mobile-satellite system having a mobile bandwidth and having mobile-satellite users communicating using the mobile bandwidth, said spread-spectrum satellite system overlaying in spectrum the mobile bandwidth for simultaneous communication of mobile-satellite satellite voice and spread-spectrum satellite paging information, said spread-spectrum satellite system comprising:

a satellite, having an antenna beamwidth overlaying the same geographical region as covered by said mobile-satellite system, for communicating data to the plurality of remote pager units;

system means for converting a format of the data into a form suitable for communicating over radio waves;

system-product means for spread-spectrum processing the converted data;

system means for transmitting across at least part of the mobile bandwidth, simultaneously and non-interferingly with a transmission from said mobile-satellite system on the same part of the mobile bandwidth, the spread-spectrum-processed-converted data from the satellite to a respective one of the plurality of remote pager units; and

a plurality of remote pager units, located within the same geographical area as covered by said mobile-satellite system, for receiving on the same part of the mobile bandwidth the spread-spectrum-processed-converted data, each of said remote pager units including,

a remote antenna; and

remote-detection means coupled to said remote antenna for recovering data communicated from said satellite.

2. The spread-spectrum satellite system as set forth in claim 1 wherein said remote-detection means includes means for converting the format of the data into a form suitable for a user.

3. The spread-spectrum satellite system as set forth in claim 1 wherein said remote-detection means includes means for generating a local spreading sequence, said local spreading sequence for comparing with signals received, to recover data sent from said satellite to said remote pager unit.

4. The spread-spectrum satellite system as set forth in claim 1 wherein said remote-detection means includes means for synchronizing a spreading sequence to received signals.

5. The spread-spectrum satellite system as set forth in claim 1 wherein said system-product-processing means includes means for processing data for a particular remote pager unit with a selected spreading sequence.

6. The spread-spectrum satellite system as set forth in claim 1 wherein said system transmitting means transmits the spread-spectrum-processed-converted data in a time division format.

7. A spread-spectrum satellite paging system for communicating data in a same geographical region as covered by a mobile-satellite system, with the mobile-satellite system having a mobile bandwidth divided into a plurality of mobile channels separated by a plurality of guard bands, respectively, and having mobile-satellite users communicating on the plurality of mobile channels, said spread-spectrum satellite paging system overlaying in spectrum the mobile bandwidth, said spread-spectrum satellite paging system comprising:

a satellite for communicating data across at least part of the mobile bandwidth, simultaneously and non-interferingly with a transmission from said mobile-satellite system on the same part of the mobile bandwidth; and

a plurality of remote units, located within the same geographical region as covered by the mobile-satellite system, for receiving the data from the satellite, each of said plurality of remote units including,

a remote antenna;

remote-filter means coupled to said remote antenna for notch filtering the plurality of mobile channels; and

remote-detection means coupled to said remote-filter means, for recovering the data communicated from said satellite.

8. The spread-spectrum satellite paging system as set forth in claim 7 wherein said remote-detection means includes means for converting a format of the data into a form suitable for a user.

9. The spread-spectrum satellite paging system as set forth in claim 7 wherein said remote-detection means includes means for generating a local spreading sequence, said local spreading sequence for comparison with signals received, to recover data sent from said satellite to said remote unit.

10. The spread-spectrum satellite paging system as set forth in claim 7 wherein said remote-detection means includes means for synchronizing a spreading sequence to received signals.

11. The spread-spectrum satellite paging system as set forth in claim 7, with said satellite including system-product-processing means for processing data for particular remote units with a selected spreading sequence.

12. The spread-spectrum satellite paging system as set forth in claim 11, with said satellite including transmitting means for transmitting the processed data to particular remote units in a time division format.

13. A remote unit for use with a spread-spectrum satellite system for receiving data from a satellite, said spread-spectrum satellite system having a plurality of remote units located within a same geographical region as covered by a mobile-satellite system, with the mobile-satellite system having a plurality of mobile-satellite users communicating on a plurality of mobile channels, said spread-spectrum satellite system overlaying in spectrum the plurality of mobile channels for communicating with the plurality of remote units simultaneously and non-interferingly with communications between the plurality of mobile-satellite users, said remote unit comprising:

a remote antenna;

a comb filter for notch filtering the plurality of mobile channels; and

a spread-spectrum receiver for recovering data communicated from said satellite.

14. A method, using a spread-spectrum satellite system, for communicating data from a satellite to a plurality of remote units, said spread-spectrum satellite system having said plurality of remote units located within a same geographical region as covered by a mobile-satellite system, with the mobile-satellite system having a mobile bandwidth and a plurality of mobile-satellite users communicating on the mobile bandwidth, said spread-spectrum satellite system communicating with said plurality of remote units simultaneously and non-interferingly with the mobile-satellite system communicating with the plurality of mobile-satellite users, and using at least part of the same mobile bandwidth, said method comprising the steps of:

converting a format of the data into a form suitable for communicating over radio waves;

spread-spectrum processing the converted data;

transmitting, from said satellite, the spread-spectrum-processed-converted-data as a data signal across at least part of the mobile bandwidth;

receiving the data signal; and

recovering, at a remote unit, the data from the data signal.

15. The method as set forth in claim 14, wherein the step of recovering the data from the data signal includes converting a format of the recovered data into a form suitable for a user.

16. The method as set forth in claim 14, wherein the step of spread-spectrum processing the converted data includes the steps of:

generating a selected spreading sequence;

comparing the selected spreading sequence to at least one received signal; and

recovering data sent from said satellite at said remote unit.

17. The method as set forth in claim 14, wherein the step of spread-spectrum processing the converted data includes synchronizing the spread-spectrum processing of the converted data to at least one received signal.

18. The method as set forth in claim 14, wherein the step of spread-spectrum processing the converted data includes processing data for a particular remote unit with a selected spreading sequence.

19. The method as set forth in claim 14, wherein the step of transmitting includes transmitting the data signal to a remote unit in a time division format.

20. A method, using a spread-spectrum receiver, for receiving spread-spectrum signals containing data at a remote unit of a spread-spectrum satellite paging system, said spread-spectrum satellite paging system having a plurality of remote units located within a same geographical region as covered by a mobile-satellite system, with the mobile satellite system having a mobile bandwidth divided into a plurality of mobile channels separated by a plurality of guard bands, respectively, and having a plurality of mobile-satellite users communicating on the plurality of mobile channels, respectively, said spread-spectrum satellite paging system communicating with said plurality of remote units simultaneously and non-interferingly with the mobile-satellite system communicating with the plurality of mobile-satellite users, and using at least part of the same mobile bandwidth, said method comprising the steps of:

receiving the spread-spectrum signals transmitted over at least a part of the mobile bandwidth;

notch filtering at the plurality of mobile channels; and

recovering the data from the spread-spectrum signals.

21. The method as set forth in claim 20 wherein the notch filtering step includes notch filtering with band rejection at the plurality of mobile channels.

22. A spread-spectrum satellite paging system for communicating paging data from a satellite to a plurality of remote pager units, said spread-spectrum satellite paging system having said plurality of remote pager units located in a same geographical region as covered by a mobile-satellite system, with the mobile-satellite system having a mobile bandwidth and having mobile-satellite users communicating using the mobile bandwidth, said spread-spectrum satellite system comprising:

a satellite, having an antenna beamwidth overlaying the same geographical region as covered by said mobile-satellite system, for communicating paging data to the plurality of remote pager units;

system means for converting a format of the paging data into a form suitable for communicating over radio waves;

system-product means for spread-spectrum processing the converted paging data as spread-spectrum-processed paging data;

system means for transmitting across the mobile bandwidth, simultaneously and non-interferingly with a transmission from said mobile-satellite system, the spread-spectrum-processed paging data from the satellite to a respective one of the plurality of remote pager units; and

a plurality of remote pager units, located within the same geographical area as covered by said mobile-satellite system, for receiving on the mobile bandwidth the spread-spectrum-processed paging data, each of said remote pager units including,

a remote antenna; and

remote-detection means coupled to said remote antenna for recovering the paging data communicated from said satellite.

23. A method, using a spread-spectrum satellite paging system, for communicating paging data from a satellite to a plurality of remote paging units, said spread-spectrum satellite system having said plurality of remote paging units located within a same geographical region as covered by a mobile-satellite system, with the mobile-satellite system having a mobile bandwidth and a plurality of mobile-satellite users communicating on a plurality of mobile channels within the mobile bandwidth, said method comprising the steps of:

converting a format of the paging data into a form suitable for communicating over radio waves;

spread-spectrum processing the converted paging data;

transmitting, from said satellite, the spread-spectrum-processed-converted-paging data as a data signal using the mobile bandwidth, said data signal transmitted simultaneously and non-interferingly with a mobile-satellite-system communication signal transmitted using the mobile bandwidth;

receiving the data signal at a remote unit;

notch filtering at the plurality of mobile channels; and

recovering, at the remote unit, the paging data from the data signal.

24. The method as set forth in claim 23, wherein the step of recovering the data from the data signal includes converting a format of the recovered data into a form suitable for a user.

25. The method as set forth in claim 23, wherein the step of transmitting includes transmitting the data signal to a remote unit in a time division format.