Filters for combined radiotelephone/GPS terminals

• US 20030143949A1
• Filed: 01/29/2003
• Published: 07/31/2003
• Est. Priority Date: 09/14/2001
• Status: Active Grant

• Current Assignee: ATC Technology Corporation (FedEx Corporation)
• Original Assignee: Mobile Satellite Venture LP
• Inventors: Karabinis, Peter D.
• Granted Patent: US 6,785,543 B2
• Time in Patent Office: Days
• US Class Current: 455/12.1
• CPC Class Codes: H04B 1/3805 with built-in auxiliary receivers
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/1853 Satellite systems for providing telephony service to a mobile station, i.e. mobile satellite service for selecting H04W
• CPC Class Codes: H04B 7/18563 Arrangements for interconnecting multiple systems data switching networks H04L12/00
• CPC Class Codes: H04B 7/216 Code division or spread-spectrum multiple access [CDMA, SSMA]
• CPC Class Codes: H04M 15/8083 involving reduced rates or discounts, e.g. time-of-day reductions or volume discounts
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 16/30 Special cell shapes, e.g. doughnuts or ring cells
• CPC Class Codes: H04W 4/24 Accounting or billing
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 72/00 Local resource management

Abstract

A satellite radiotelephone system includes a space-based component, a plurality of ancillary terrestrial components, and a plurality of radiotelephones. The space-based component is configured to provide wireless radiotelephone communications using satellite radiotelephone frequencies. The plurality of ancillary terrestrial components include a plurality of ancillary terrestrial component antennas configured to provide wireless radiotelephone communications using at least one of the satellite radiotelephone frequencies in a radiation pattern that increases radiation below the horizon compared to above the horizon. The plurality of radiotelephones are configured to communicate with the space-based component and with the plurality of ancillary terrestrial components. Each radiotelephone also includes a GPS signal processor and a GPS mode filter that is configured to suppress energy at (1575.42−Δ) MHz, where 0<Δ≦16.42 MHz. Related radiotelephones and methods are also discussed.

Claims

1. A satellite radiotelephone system comprising:

a space-based component that is configured to provide wireless radiotelephone communications using satellite radiotelephone frequencies;

a plurality of ancillary terrestrial components including a plurality of ancillary terrestrial component antennas that are configured to provide wireless radiotelephone communications using at least one of the satellite radiotelephone frequencies in a radiation pattern that increases radiation below the horizon compared to above the horizon; and

a plurality of radiotelephones that are configured to communicate with the space-based component and with the plurality of ancillary terrestrial components, the radiotelephones also including a GPS signal receiver and a GPS mode filter that is configured to suppress energy at and/or below (1575.42−

Δ

) MHz, where 0<

Δ

≦

16.42 MHz.

2. The satellite radiotelephone system according to claim 1, wherein the GPS mode filter is configured to suppress at least 10 dB of energy at and/or below (1575.42−

Δ

) MHz.

3. The satellite radiotelephone system according to claim 2, wherein the GPS mode filter is configured to suppress at least 10 dB of energy at frequencies less than (1575.42−

Δ

) MHz.

4. The satellite radiotelephone system according to claim 1, wherein the GPS mode filter is configured to suppress at least 10 dB of energy at and below (1575.42−

Δ

) MHz.

5. The satellite radiotelephone system according to claim 1, wherein the radiotelephones are further configured to suppress processing of GPS signals when actively communicating with the space-based component and/or one of the ancillary terrestrial components.

6. The satellite radiotelephone system according to claim 5, wherein the GPS mode filter is coupled between an antenna and a low noise amplifier used in reception of GPS signals.

7. The satellite radiotelephone system according to claim 1, wherein the satellite radiotelephone frequencies comprise a satellite downlink frequency band and a satellite uplink frequency band and wherein GPS signals are transmitted from GPS satellites over a GPS frequency band between the satellite downlink and uplink frequency bands.

8. The satellite radiotelephone system according to claim 7, wherein the satellite downlink frequency band comprises frequencies between 1525 MHz and 1559 MHz, and wherein the satellite uplink frequency band comprises frequencies between 1626.5 MHz and 1660.5 MHz.

9. The satellite radiotelephone system according to claim 7, wherein the GPS frequency band comprises frequencies between 1559 MHz and 1605 MHz.

10. The satellite radiotelephone system according to claim 1, wherein Δ

is greater than at least 1 MHz.

11. The satellite radiotelephone system according to claim 1, wherein the wireless radiotelephone communications are not subjected to the GPS mode filter.

12. The satellite radiotelephone system according to claim 1, wherein the GPS mode filter comprises a high pass filter.

13. The satellite radiotelephone system according to claim 1, wherein the radiotelephones are further configured to receive incoming call pages during GPS mode operations.

14. A radiotelephone comprising:

a radio front end that is configured to provide wireless radiotelephone communications using radiotelephone frequencies, and that is configured to receive global positioning satellite (GPS) signals from a plurality of global positioning satellites;

a signal processor that is configured to determine a measure of location of the radiotelephone using GPS signals received at the radio front end when providing GPS mode operations and that is configured to process communications that are received at and/or transmitted from the radio front end when providing wireless radiotelephone communications; and

a GPS mode filter that is configured to filter GPS signals received at the radio front end before being provided to the signal processor, wherein the GPS mode filter is configured to suppress energy at and/or below (1575.42−

Δ

) MHz, where 0<

Δ

≦

16.42 MHz.

15. The radiotelephone according to claim 14, wherein the radio front end is configured to provide radiotelephone communications with a space-based component using satellite radiotelephone frequencies and to provide wireless radiotelephone communications with a plurality of ancillary terrestrial components using at least one of the satellite radiotelephone frequencies.

16. The radiotelephone according to claim 14, wherein the wireless radiotelephone communications are not subjected to the GPS mode filter.

17. The radiotelephone according to claim 14, wherein the GPS mode filter is coupled between an antenna and a low noise amplifier used in reception of GPS signals.

18. The radiotelephone according to claim 14, wherein the GPS mode filter is configured to suppress at least 10 dB at (1575.42−

Δ

) MHz.

19. The radiotelephone according to claim 18, wherein the GPS mode filter is configured to suppress at least 10 dB of energy at frequencies less than (1575.42−

Δ

) MHz.

20. The radiotelephone according to claim 14, wherein processing of GPS signals at the signal processor is suppressed when actively providing radiotelephone communications with the space-based component and/or one of the ancillary terrestrial components.

21. The radiotelephone according to claim 14, wherein the satellite radiotelephone frequencies comprise a satellite downlink frequency band and a satellite uplink frequency band and wherein GPS signals are transmitted from GPS satellites over a GPS frequency band between the satellite downlink and uplink frequency bands.

22. The radiotelephone according to claim 21, wherein the satellite downlink frequency band comprises frequencies between 1525 MHz and 1559 MHz, and wherein the satellite uplink frequency band comprises frequencies between 1626.5 MHz and 1660.5 MHz.

23. The radiotelephone according to claim 21, wherein the GPS frequency band comprises frequencies between 1559 MHz and 1605 MHz.

24. The radiotelephone according to claim 14, wherein Δ

is greater than at least 1 MHz.

25. The radiotelephone according to claim 14, wherein the GPS mode filter comprises a high pass filter.

26. The radiotelephone according to claim 14, wherein the radio front end is further configured to receive incoming call pages during GPS mode operations and wherein the signal processor is further configured to process incoming call pages during GPS operations.

27. A method of providing radiotelephone communications at a radiotelephone comprising a radio front end that is configured to provide wireless radiotelephone communications using radiotelephone frequencies, and that is configured to receive global positioning satellite (GPS) signals from a plurality of Global positioning satellites, the method comprising:

during GPS mode operations, suppressing energy at and/or below (1575.42−

Δ

) MHz for GPS signals received from the radio front end, where 0<

Δ

≦

16.42 MHz;

during GPS mode operations, determining a measure of location of the radiotelephone using the GPS signals having suppressed energy at and/or below (1575.42−

Δ

) MHz; and

during wireless radiotelephone communications, processing communications that are received at and/or transmitted from the radio front end.

28. The method according to claim 27, wherein the radio front end is configured to provide wireless radiotelephone communications with a space-based component using satellite radiotelephone frequencies and to provide wireless radiotelephone communications with a plurality of ancillary terrestrial components using at least one of the satellite radiotelephone frequencies

29. The method according to claim 27, wherein processing communications that are received at and transmitted from the radio front end during wireless radiotelephone communications comprises processing the communications without suppressing energy of the communications at and/or below (1575.42−

Δ

) MHz.

30. The method according to claim 27, wherein suppressing energy at and/or below (1575.42−

Δ

) MHz comprises suppressing at least 10 dB of energy at and/or below (1575.42−

Δ

) MHz.

31. The method according to claim 30, wherein suppressing energy at and/or (1575.42−

Δ

) MHz comprises suppressing at least 10 dB of energy at frequencies less than (1575.42−

Δ

) MHz.

32. The method according to claim 31, wherein suppressing energy at and/or below (1575.42−

Δ

) MHz comprises suppressing at least 10 dB of energy at (1575.42−

Δ

) MHz and at frequencies less than (1575.42−

Δ

) MHz.

33. The method according to claim 27, wherein processing of GPS signals is suppressed when actively providing radiotelephone communications with the space-based component and/or one of the ancillary terrestrial components.

34. The method according to claim 28, wherein the satellite radiotelephone frequencies comprise a satellite downlink frequency band and a satellite uplink frequency band and wherein GPS signals are transmitted from GPS satellites over a GPS frequency band between the satellite downlink and uplink frequency bands.

35. The method according to claim 34, wherein the satellite downlink frequency band comprises frequencies between 1525 MHz and 1559 MHz, and wherein the satellite uplink frequency band comprises frequencies between 1626.5 MHz and 1660.5 MHz.

36. The method according to claim 34, wherein the GPS frequency band comprises frequencies between 1559 MHz and 1605 MHz.

37. The method according to claim 27, wherein Δ

is greater than at least 1 MHz.

38. The method according to claim 27, further comprising:

receiving an incoming call page during GPS mode operations; and

processing the incoming call page during GPS operations.

39. The method according to claim 27, further comprising:

during GPS mode operations prior to determining the measure of location, providing low noise amplification of the GPS signals having suppressed energy at and/or below (1575.42−

Δ

) MHz.