ADAPTIVE TRANSMISSION (TX)/RECEPTION (RX) PULSE SHAPING FILTER FOR FEMTOCELL BASE STATIONS AND MOBILE STATIONS WITHIN A NETWORK

• US 20100048215A1
• Filed: 08/11/2009
• Published: 02/25/2010
• Est. Priority Date: 08/20/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Lin, Yu-Chuan, Yavuz, Mehmet, Tokgoz, Yeliz
• Granted Patent: US 8,437,762 B2
• Time in Patent Office: Days
• US Class Current: 455/444
• CPC Class Codes: H04L 25/03834 using pulse shaping
• CPC Class Codes: H04W 36/0064 of control information between different access points
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

A mobile station may include a standard transmit pulse-shaping filter, a standard receive pulse-shaping filter, a narrower transmit pulse-shaping filter, and a narrower receive pulse-shaping filter. A femtocell base station may include a narrower transmit pulse-shaping filter and a narrower receive pulse-shaping filter. The mobile station may utilize the narrower transmit pulse-shaping filter for transmitting uplink signals and the narrower receive pulse-shaping filter for receiving downlink signals when it is receiving service from the femtocell base station. The mobile station may utilize the standard transmit pulse-shaping filter for transmitting uplink signals and the standard receive pulse-shaping filter for receiving downlink signals when it is receiving service from a macrocell base station.

Claims

1. A femtocell base station that is configured for limiting adjacent channel interference, comprising:

a transmitter for transmitting downlink signals to a first mobile station, wherein the first mobile station is located within a femtocell; and

a narrower transmit pulse-shaping filter, wherein the narrower transmit pulse-shaping filter is configured so that a bandwidth of the downlink signals that are transmitted by the femtocell base station is less than a bandwidth of downlink signals that are transmitted by a macrocell base station to a second mobile station.

2. The femtocell base station of claim 1, further comprising:

a receiver for receiving uplink signals from the first mobile station; and

a narrower receive pulse-shaping filter that matches a narrower transmit pulse-shaping filter at the first mobile station.

3. The femtocell base station of claim 2, wherein the narrower transmit pulse-shaping filter at the first mobile station is configured so that a bandwidth of the uplink signals that are transmitted by the first mobile station is less than a bandwidth of uplink signals that are transmitted by the second mobile station to the macrocell base station.

4. The femtocell base station of claim 1, wherein a narrower receive pulse-shaping filter at the first mobile station matches the narrower transmit pulse-shaping filter.

5. The femtocell base station of claim 1, wherein the macrocell base station covers a macrocell, and wherein the femtocell is located within the macrocell.

6. The femtocell base station of claim 1, wherein the second mobile station is also located within the femtocell.

7. A mobile station that is configured for limiting adjacent channel interference, comprising:

a transmitter for transmitting uplink signals;

a transmit pulse-shaping filter that limits bandwidth of the uplink signals transmitted by the mobile station; and

a narrower transmit pulse-shaping filter that limits the bandwidth of the uplink signals transmitted by the mobile station to a greater extent than the transmit pulse-shaping filter.

8. The mobile station of claim 7, further comprising a switching mechanism for switching between the transmit pulse-shaping filter and the narrower transmit pulse-shaping filter.

9. The mobile station of claim 8, wherein the switching mechanism is configured to switch from the transmit pulse-shaping filter to the narrower transmit pulse-shaping filter in response to detecting that a handoff from a macrocell base station to a femtocell base station has occurred.

10. The mobile station of claim 8, wherein the switching mechanism is configured to switch from the narrower transmit pulse-shaping filter to the transmit pulse-shaping filter in response to detecting that a handoff from a femtocell base station to a macrocell base station has occurred.

11. The mobile station of claim 7, further comprising:

a receiver for receiving downlink signals;

a receive pulse-shaping filter that matches a transmit pulse-shaping filter at a macrocell base station; and

a narrower receive pulse-shaping filter that matches a narrower transmit pulse-shaping filter at a femtocell base station.

12. The mobile station of claim 11, further comprising a switching mechanism for switching between the receive pulse-shaping filter and the narrower receive pulse-shaping filter.

13. The mobile station of claim 12, wherein the switching mechanism is configured to switch from the receive pulse-shaping filter to the narrower receive pulse-shaping filter in response to detecting that a handoff from the macrocell base station to the femtocell base station has occurred.

14. The mobile station of claim 12, wherein the switching mechanism is configured to switch from the narrower receive pulse-shaping filter to the receive pulse-shaping filter in response to detecting that a handoff from the femtocell base station to the macrocell base station has occurred.

15. A method for increasing the signal-to-noise ratio (SNR) with respect to a received signal and for limiting adjacent uplink channel interference, the method being implemented by a mobile station, the method comprising:

detecting that a handoff from a macrocell base station to a femtocell base station has occurred;

switching from a receive pulse-shaping filter to a narrower receive pulse-shaping filter; and

using the narrower receive pulse-shaping filter to receive downlink transmissions from the femtocell base station.

16. The method of claim 15, wherein the narrower receive pulse-shaping filter matches a narrower transmit pulse-shaping filter at the femtocell base station.

17. The method of claim 15, further comprising:

switching from a transmit pulse-shaping filter to a narrower transmit pulse-shaping filter; and

using the narrower transmit pulse-shaping filter to send uplink transmissions to the femtocell base station.

18. The method of claim 17, wherein the narrower transmit pulse-shaping filter limits a bandwidth of the uplink transmissions to a greater extent than the transmit pulse-shaping filter.

19. The method of claim 15, further comprising:

detecting that a handoff from the femtocell base station to the macrocell base station has occurred;

switching from the narrower receive pulse-shaping filter to the receive pulse-shaping filter; and

using the receive pulse-shaping filter to receive downlink transmissions from the macrocell base station.

20. The method of claim 19, further comprising:

switching from a narrower transmit pulse-shaping filter to a transmit pulse-shaping filter; and

using the transmit pulse-shaping filter to send uplink transmissions to the macrocell base station.

21. An apparatus that is configured to increase the signal-to-noise ratio (SNR) with respect to a received signal and to limit adjacent uplink channel interference, comprising:

means for detecting that a handoff from a macrocell base station to a femtocell base station has occurred;

means for switching from a receive pulse-shaping filter to a narrower receive pulse-shaping filter; and

means for using the narrower receive pulse-shaping filter to receive downlink transmissions from the femtocell base station.

22. The apparatus of claim 21, wherein the narrower receive pulse-shaping filter matches a narrower transmit pulse-shaping filter at the femtocell base station.

23. The apparatus of claim 21, further comprising:

means for switching from a transmit pulse-shaping filter to a narrower transmit pulse-shaping filter; and

means for using the narrower transmit pulse-shaping filter to send uplink transmissions to the femtocell base station.

24. The apparatus of claim 23, wherein the narrower transmit pulse-shaping filter limits a bandwidth of the uplink transmissions to a greater extent than the transmit pulse-shaping filter.

25. The apparatus of claim 21, further comprising:

means for detecting that a handoff from the femtocell base station to the macrocell base station has occurred;

means for switching from the narrower receive pulse-shaping filter to the receive pulse-shaping filter; and

means for using the receive pulse-shaping filter to receive downlink transmissions from the macrocell base station.

26. The apparatus of claim 25, further comprising:

means for switching from a narrower transmit pulse-shaping filter to a transmit pulse-shaping filter; and

means for using the transmit pulse-shaping filter to send uplink transmissions to the macrocell base station.

27. A computer-program product for increasing the signal-to-noise ratio (SNR) with respect to a received signal and for limiting adjacent uplink channel interference, the computer-program product comprising a computer-readable medium having instructions thereon, the instructions comprising:

code for detecting that a handoff from a macrocell base station to a femtocell base station has occurred;

code for switching from a receive pulse-shaping filter to a narrower receive pulse-shaping filter; and

code for using the narrower receive pulse-shaping filter to receive downlink transmissions from the femtocell base station.

28. The computer-program product of claim 27, further comprising:

code for switching from a transmit pulse-shaping filter to a narrower transmit pulse-shaping filter; and

code for using the narrower transmit pulse-shaping filter to send uplink transmissions to the femtocell base station.

29. The computer-program product of claim 27, further comprising:

code for detecting that a handoff from the femtocell base station to the macrocell base station has occurred;

code for switching from the narrower receive pulse-shaping filter to the receive pulse-shaping filter; and

code for using the receive pulse-shaping filter to receive downlink transmissions from the macrocell base station.

30. The computer-program product of claim 29, further comprising:

code for switching from a narrower transmit pulse-shaping filter to a transmit pulse-shaping filter; and

code for using the transmit pulse-shaping filter to send uplink transmissions to the macrocell base station.