Systems and methods for reusing a low noise amplifier in a wireless communications device

• US 7,356,314 B2
• Filed: 04/17/2003
• Issued: 04/08/2008
• Est. Priority Date: 04/17/2003
• Status: Expired due to Fees

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Wireless Corporation (Kyocera Corporation)
• Inventors: Tran, Allen, Forrester, Tim
• Primary Examiner(s): Nguyen; Quynh H.
• Application Number:
  US10/417,882
• Publication Number:
  US 20040209583A1
• Time in Patent Office: 1,818 Days
• Field of Search: 455/553, 455/103, 455/188.1, 455/107, 455/168.1, 455/226.3, 455/266, 455/296
• US Class Current: 455/103
• CPC Class Codes: H03F 2200/294 the amplifier being a low noise amplifier [LNA]
• CPC Class Codes: H03F 2200/372 Noise reduction and elimination in amplifier
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence
• CPC Class Codes: H04B 1/3805 with built-in auxiliary receivers
• CPC Class Codes: H04B 1/406 with more than one transmission mode, e.g. analog and digital modes

Abstract

A wireless communication device comprises a plurality of receive signal paths, each of the receive signal paths is configured to receive signals in a certain frequency bandwidth. The communication device also comprises an amplifier coupled with each of the plurality of receive signal paths. The amplifier is configured to amplify the receive signals associated with each of the plurality of receive signal paths.

Claims

1. A method of configuring a wireless communication device to receive signals in a plurality of signal bands, comprising:

determining a required gain for each of the plurality of signal bands;

determining a required noise figure for each of the plurality of signal bands;

determining an impedance for each of the plurality of signal bands as seen by a single amplifier that will approximately result in the required gain and noise figure for each of the plurality of receive signals when amplified by the amplifier;

configuring receive signal paths associated with each of the plurality of signal bands so that the appropriate determined impedances are presented to the amplifier when the amplifier is receiving signals in a particular signal band;

selecting an input impedance of the amplifier to broaden a pass band of the amplifier; and

offsetting any reduction in noise figure for each of the receive signal paths by reducing the insertion loss for each of the receive signal paths by configuring the wireless communication device to use a single image rejection filter.

2. The method of claim 1, wherein reducing the insertion loss comprises configuring the wireless communication device to use a N-plexer.

3. The method of claim 1, wherein reducing the insertion loss comprises configuring the wireless communication device to use a triplexer.

4. The method of claim 1, further comprising determining a pass band center frequency near the frequency of one of the plurality of receive signal bands and configuring the amplifier to have a pass band near the determined pass band center frequency.

5. The method of claim 4, wherein configuring the amplifier comprises shifting the pass band center frequency down with a filter so that receive signals received at lower frequencies receive greater amplification.

6. The method of claim 4, wherein configuring the amplifier comprises shifting the pass band center frequency up with a filter so that receive signals received at higher frequencies receive greater amplification.

7. The method of claim 4, wherein the wireless communication device is configured to receive a high frequency receive signal, a mid frequency receive signal, and a low frequency receive signal, and wherein configuring the amplifier comprises configuring the amplifier to have a pass band center frequency near a frequency band associated with the low frequency receive signal.

8. The method of claim 4, wherein the wireless communication device is configured to receive a high frequency receive signal, a mid frequency receive signal, and a low frequency receive signal, and wherein configuring the amplifier comprises configuring the amplifier to have a pass band center frequency near a frequency band associated with the high frequency receive signal.

9. The method of claim 4, wherein the wireless communication device is configured to receive a high frequency receive signal, a mid frequency receive signal, and a low frequency receive signal, and wherein configuring the amplifier comprises configuring the amplifier to have a pass band center frequency near a frequency band associated with the mid frequency receive signal.

10. A wireless communication device, comprising:

a single amplifier having an input for receiving signals and an output, the amplifier configured, by selecting an input impedance of the amplifier to broaden a pass band of the amplifier, to amplify received signals associated with each of a plurality of receive signal paths including the amplifier, each receive signal path configured to receive signals in a corresponding frequency band having a required gain and a required noise figure, the plurality of receive signal paths configured to present an impedance to the amplifier resulting in the required gain and required noise figure of the receive band corresponding to the received signals being amplified by the amplifier; and

a single image rejection filter coupled with the amplifier output, the single image rejection filter configured to filter the amplified received signals generated by the amplifier to offset any reduction in noise figure for each of the receive signal paths by reducing the insertion loss for each of the receive signal paths.

11. The wireless communication device of claim 10, further comprising a plurality of discrete image rejection filters integrated into the single image rejection filter and coupled with the amplifier output, each of the plurality of discrete image rejection filters associated with one of the plurality of receive signal paths.

12. The wireless communication device of claim 10, wherein the single image rejection filter is a FBAR device.

13. The wireless communication device of claim 10, wherein the amplifier is a low noise amplifier.

14. The wireless communication device of claim 10, further comprising:

an antenna configured to transmit and receive the signals in the plurality of communication bands and connected to the plurality of receive signal paths.

15. The wireless communication device of claim 14, wherein the antenna is configured to receive GPS signals in the GPS band.

16. The wireless communication device of claim 14, wherein the antenna is configured to receive PCS signals in the PCS band.

17. The wireless communication device of claim 14, wherein the antenna is configured to receive cellular signals in the cellular band.

18. The wireless communication device of claim 14, wherein the single image rejection filter is a FBAR device.

19. The wireless communication device of claim 14, wherein the amplifier is a low noise amplifier.

20. A wireless communication device, comprising:

a plurality of receive paths comprising a single rejection filter connected to an output of a single amplifier having an amplifier input impedance, each receive path having a noise figure and a gain within a frequency bandwidth, the plurality of receive paths configured to present a receive path impedance less than the amplifier input impedance to an input of the amplifier to broaden a pass band of the amplifier and configured to at least partially offset reduction in noise figure and gain due to a mismatch between the receive path impedance and the amplifier input impedance to maintain the gain and noise figure for each corresponding frequency bandwidth to be greater than or equal to the minimum gain and minimum noise figure for receiving the signals within the corresponding frequency bandwidth.