Modem with exclusively selectable echo canceller and high pass filter for near-end signal removal

• US 20070002940A1
• Filed: 06/30/2005
• Published: 01/04/2007
• Est. Priority Date: 06/30/2005
• Status: Abandoned Application

• Current Assignee: Silicon Laboratories Incorporated
• Original Assignee: Silicon Laboratories Incorporated
• Inventors: Zhou, Yan
• Application Number:
  US11/173,997
• Publication Number:
  US 20070002940A1
• Time in Patent Office: Days
• US Class Current: 375/222
• CPC Class Codes: H04B 3/23 using a replica of transmitted signal in the time domain, e.g. echo cancellers
• CPC Class Codes: H04L 1/0054 Maximum-likelihood or sequential decoding, e.g. Viterbi, Fano, ZJ algorithms
• CPC Class Codes: H04L 1/0065 Serial concatenated codes

Abstract

A communication apparatus includes a modem coupled to a subscriber line carrying a composite signal. The composite signal includes a near-end transmitted signal and a far-end transmitted signal. The modem includes a high pass filter and an echo canceller. The composite signal is exclusively provided to a selected one of the echo canceller and the high pass filter to remove a near-end transmitted signal from the composite signal.

Claims

1. A communication apparatus, comprising:

a modem coupled to a subscriber line carrying a composite signal, the composite signal including a near-end transmitted signal and a far-end transmitted signal, the modem comprising;

a high pass filter; and

an echo canceller, wherein the composite signal is exclusively provided to a selected one of the echo canceller and the high pass filter for removing the near-end transmitted signal from the composite signal.

2. The apparatus of claim 1 wherein the composite signal includes digital data as a discrete multi-tone modulated signal.

3. The apparatus of claim 1 wherein the near-end transmitted signal and the far-end transmitted signal are frequency division multiplexed within the composite signal.

4. The apparatus of claim 1 wherein the echo canceller is a digital echo canceller.

5. The apparatus of claim 1 wherein the high pass filter is a digital high pass filter.

6. A method of data communication, comprising:

(a) providing a subscriber line carrying a near-end transmitted signal and a far-end transmitted signal as a composite signal; and

(b) providing the composite signal to an exclusively selected one of an echo canceller and a high pass filter for removal of the near-end transmitted signal.

7. The method of claim 6 wherein the composite signal includes digital data as a discrete multi-tone modulated signal.

8. The method of claim 6 wherein the near-end transmitted signal and the far-end transmitted signal are frequency division multiplexed within the composite signal.

9. The method of claim 6 wherein the echo canceller is a digital echo canceller.

10. The method of claim 6 wherein the high pass filter is a digital high pass filter.