Method and apparatus for reception of terrestrial digital television signals

• US 7,034,893 B2
• Filed: 08/06/2001
• Issued: 04/25/2006
• Est. Priority Date: 03/30/2001
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Liu, Tianmin, Perlow, Randall B.
• Primary Examiner(s): Natnael, Paulos M.
• Application Number:
  US09/923,676
• Publication Number:
  US 20020163593A1
• Time in Patent Office: 1,723 Days
• Field of Search: 348/614, 348/611, 348/607, 348/706, 348/705, 348/725, 348/729, 348/731, 375/321, 375/347, 375/267, 455/132, 455/133, 455/138, 455/277.1, 455/277.2, 455/278.1, 455/279.1
• US Class Current: 348/614
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 2025/03426 transmission using multiple-input and multiple-output channels
• CPC Class Codes: H04L 25/03057 with a recursive structure H04L25/03031 takes precedence
• CPC Class Codes: H04L 27/06 Demodulator circuits; Receiver circuits
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 5/211 Ghost signal cancellation H04N23/81 takes precedence

Abstract

A digital television signal is intercepted by a plurality of antennas to produce a corresponding plurality of input signals. The antennas have different directionality so they can be combined in a way that reduces multipath echoes. In one embodiment, the antennas are arranged to operate in a diversity or scanned array mode. In another embodiment, the antennas are arranged to operate in a adaptive phased array mode. The input signals intercepted by the antenna are subjected to vestigial sideband (VSB) processing to produce a single VSB processed signal, which is decoded to form a display drive signal. A plurality of input signals in a VSB receiver having a plurality of antennas with different directionality are evaluated to determine how the input signals should be combined to reduce multipath echoes. The quality of the input signals from the antennas is evaluated at one of a number of different points in the VSB receiver, such as at the outputs of the antennas, the outputs of the VSB processors, or the output of the forward error correction (FEC) decoder. Within the VSB processors themselves, the quality of the input signals can be evaluated at a number of different points, including the outputs at the front end, the outputs at the back end, or inside the back end the outputs at the feed forward equalizer.

Claims

1. A receiver for intercepting a modulated radio signal in a first mode or and second mode, the receiver comprising:

first and second antennas having different directionality to produce corresponding first and second input signals;

means for evaluating the quality of the first and second input signals;

first and second signal processors connected to the one or both of the first and second antennas for demodulating the respective first and second input signals;

a tuner in each of the first and second signal processors, the tuners being set to different frequencies in the first mode and the same frequency in the second mode;

a utilization circuit;

means in the first mode for connecting both of the signal processors to the utilization circuit irrespective of the quality of the input signals; and

means responsive to the evaluating means in the second mode for connecting one of the signal processors to the utilization circuit based on the quality of the input signals, the first and second modes operating alternatively.

2. The receiver of claim 1, in which the connecting means responsive to the evaluating means in the second mode comprises a switch.

3. The receiver of claim 2, in which the utilization circuit has forward error correction means.

4. The receiver of claim 2, additionally comprising an equalizer and a signal slicer in each signal processor.

5. The receiver of claim 1, additionally comprising an equalizer and a signal slicer in each signal processor.