Direct conversion receiver capable of supporting multiple standard specifications in a mobile communication system

• US 20030072320A1
• Filed: 09/09/2002
• Published: 04/17/2003
• Est. Priority Date: 10/13/2001
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Seo, Hae-Moon, Lim, Hyoung-Kil, Lee, Young-Kon
• Application Number:
  US10/237,418
• Publication Number:
  US 20030072320A1
• Time in Patent Office: Days
• US Class Current: 370/441
• CPC Class Codes: H04B 1/30 for homodyne or synchrodyne receivers demodulator circuits H03D1/22
• CPC Class Codes: H04B 1/406 with more than one transmission mode, e.g. analog and digital modes

Abstract

Disclosed is a direct conversion receiver capable of supporting multiple standard specifications in mobile communication systems. A mode switch selects a received signal having a specific standard specification from received signals according to a mode selection signal. A low-noise amplifier is turned on in response to the mode selection signal, and low-noise amplifies the signal selected by the mode switch. A frequency down-converter frequency down-converts the low-noise amplified signal to a frequency corresponding to the specific standard specification. A high-pass filter bank high-pass filters the frequency down-converted signal. A programmable analog-to-digital converter converts the high-pass filtered signal into a sampling frequency corresponding to the specific standard specification. A digital filter digital-filters the converted digital signal using a decimation rate and a filter bandwidth corresponding to the specific standard specification. A digital signal processor generates the mode selection signal, and a control signal for generating the sampling frequency.

Claims

1. A direct conversion receiver capable of supporting multiple standard specifications in mobile communication systems, comprising:

a mode switch for selecting a received signal having a specific standard specification from received signals according to a mode selection signal;

a low-noise amplifier being turned on in response to the mode selection signal, for low-noise amplifying the received signal selected by the mode switch;

a frequency down-converter for frequency down-converting the low-noise amplified signal into a frequency corresponding to the specific standard specification;

a high-pass filter bank for high-pass filtering the frequency down-converted signal;

a programmable analog-to-digital converter for converting the high-pass filtered signal into a sampling frequency corresponding to the specific standard specification;

a digital filter for digital-filtering the converted digital signal using a decimation rate and a filter bandwidth corresponding to the specific standard specification; and

a digital signal processor for generating the mode selection signal for selecting a desired standard specification signal from the received signals, and generating a control signal for generating the sampling frequency.

2. The direct conversion receiver of claim 1, wherein the high-pass filter bank is comprised of a plurality of high-pass filters for the respective standard specifications.

3. The direct conversion receiver of claim 1, wherein the digital filter comprises:

a comb filter for acquiring a decimation rate of an input signal;

an FIR (Finite Impulse Response) filter for performing channel selection on the received signal; and

a droop compensation filter for compensating for non-ideal effects of the input signal.

4. The direct conversion receiver of claim 1, wherein the multiple standard specifications include a WCDMA (Wideband Code Division Multiple Access) standard specification, a CDMA2000 standard specification, and a TD-SCDMA (Time Division-Synchronous Code Division Multiple Access) standard specification.

5. The direct conversion receiver of claim 4, wherein the mode switch provides time division duplexing (TDD) when the specific standard specification is the TD-SCDMA standard specification.

6. The direct conversion receiver of claim 1, further comprising a duplexer for canceling an interference component from the output signal of the mode switch.

7. The direct conversion receiver of claim 1, further comprising a filter for canceling an interference component from the output signal of the mode switch.

8. The direct conversion receiver of claim 1, further comprising a programmable divider for generating a sampling frequency for the specific standard specification for the programmable analog-to-digital converter according to the mode selection signal from the digital signal processor.

9. A direct conversion receiver capable of supporting multiple standard specifications in a mobile communication system, comprising:

an RF (Radio Frequency) front-end part for selecting a received signal having a specific standard specification from received signals according to a mode selection signal, and low-noise amplifying the selected received signal;

a frequency down-conversion part for frequency down-converting the low-noise amplified signal to a frequency corresponding to the specific standard specification; and

a baseband part for high-pass filtering the frequency down-converted signal, and converting the high-pass filtered signal to a sampling frequency corresponding to the specific standard specification.

10. The direct conversion receiver of claim 9, wherein the RF front-end part comprises:

a mode switch for selecting a received signal having a specific standard specification from the received signals according to the mode selection signal; and

a low-noise amplifier being turned on in response to the mode selection signal, for low-noise amplifying the received signal selected by the mode switch.

11. The direct conversion receiver of claim 9, wherein the frequency down-conversion part comprises:

a frequency synthesizer for generating a frequency corresponding to the specific standard specification; and

a down-converter for multiplying the frequency generated by the frequency synthesizer by the low-noise amplified signal.

12. The direct conversion receiver of claim 9, wherein the baseband part comprises:

a high-pass filter bank for high-pass filtering the frequency down-converted signal;

a programmable analog-to-digital converter for converting the high-pass filtered signal to a sampling frequency corresponding to the specific standard specification;

a digital filter for digital filtering the converted digital signal using a decimation rate and a filter bandwidth corresponding to the specific standard specification; and

a digital signal processor for generating the mode selection signal for selecting a desired standard specification signal from the received signals, and generating a control signal for generating the sampling frequency.

13. The direct conversion receiver of claim 12, wherein the high-pass filter bank is comprised of a plurality of high-pass filters each corresponding to one of the respective standard specifications.

14. The direct conversion receiver of claim 12, wherein the digital filter comprises:

a comb filter for acquiring a decimation rate of an input signal;

an FIR (Finite Impulse Response) filter for performing channel selection on the input signal; and

a droop compensation filter for compensating for non-ideal effects of the input signal.

15. The direct conversion receiver of claim 10, wherein the multiple standard specifications include a WCDMA (Wideband Code Division Multiple Access) standard specification, a CDMA2000 standard specification, and a TD-SCDMA (Time Division-Synchronous Code Division Multiple Access) standard specification.

16. The direct conversion receiver of claim 15, wherein the mode switch provides time division duplexing (TDD) when the specific standard specification is the TD-SCDMA standard specification.

17. The direct conversion receiver of claim 10, further comprising a duplexer for canceling an interference component from the output signal of the mode switch.

18. The direct conversion receiver of claim 10, further comprising a filter for canceling an interference component from the output signal of the mode switch.

19. The direct conversion receiver of claim 12, further comprising a programmable divider for generating a sampling frequency of the specific standard specification for the programmable analog-to-digital converter according to the mode selection signal from the digital signal processor.