Radio frequency distribution network system

• US 7,102,699 B2
• Filed: 03/14/2002
• Issued: 09/05/2006
• Est. Priority Date: 03/14/2002
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Rodolico, Joseph T.
• Primary Examiner(s): Kostak, Victor R.
• Application Number:
  US10/098,305
• Publication Number:
  US 20030177499A1
• Time in Patent Office: 1,636 Days
• Field of Search: 348/723, 348/724, 348/552, 348/705, 348/706, 725/74, 725/78, 725/80, 725/82, 725/85, 725/133, 710/9, 710/11, 710/36, 710/38, 710 62- 64, 455/3.04, 455/3.05, 455/500, 455/509, 370/343, 370/344
• US Class Current: 348/723
• CPC Class Codes: H04N 7/106 for domestic distribution

Abstract

A consumer electronic device includes circuitry configured to produce a signal corresponding to a selected one of first, second and third radio frequency channel. The circuitry includes a modulator configured to modulate the video signal such that it falls within a first predetermined frequency range, corresponding to the selected channel. The respective frequency ranges for the first, second and third radio frequency channels are mutually exclusive. Multiple consumer electronic devices are coupled to a combiner which generates a combined signal including the modulated signals from all of the devices. This signal is distributed to a plurality of receivers such that each receiver can receive any of the modulated signals without interference from any of the other modulated signals. The device may also be implemented as a stand-alone device that receives baseband signals, modulates the signals and combines the modulated signals to produce the combined signal.

Claims

1. A consumer electronic device comprising:

circuitry configured to transmit a respective signal corresponding to a respective one of at least three radio frequency channels, the circuitry including;

a modulator configured to modulate said signal such that each modulated signal includes first signal components in a predetermined frequency range corresponding to a selected one of the at least three radio frequency channels and second signal components that extend beyond the predetermined frequency range at frequencies higher and lower than the predetermined frequency range to overlap the respective predetermined frequency range of at least one adjacent one of the at least three radio frequency channels, and

at least one notch filter configured to filter from said modulated signal a portion of the second components of the modulated signal exclusive of the first signal components

wherein the modulator for a lowest one of the at least three radio frequency channels does not have a notch filter for filtering the second components of the modulated signal that extend beyond the predetermined frequency range at lower frequencies.

2. A consumer electronic video device according to claim 1 wherein said consumer electronic device is a video device, and said signal is a video signal.

3. A consumer electronic video device according to claim 2 wherein said consumer electronic video device is selected from the group consisting of video cassette recorders, digital video disc players, gaming units, satellite set tops and cable set tops.

4. A radio frequency signal distribution network, said network comprising:

a plurality of consumer electronic video devices, each of said devices including circuitry configured to transmit a first video signal corresponding to a selected one of a plurality of radio frequency channels, the circuitry including;

a modulator configured to modulate said video signal such that the modulated video signal includes first signal components in a predetermined frequency range corresponding to a respective one of the plurality of radio frequency channels and second signal components that extend beyond the predetermined frequency range at frequencies higher and lower than the predetermined frequency range to overlap the respective predetermined frequency range of at least one adjacent one of the plurality of radio frequency channels, and

at least one notch filter configured to reduce, in amplitude, a portion of the second components of the modulated video signal exclusive of the first signal components, wherein the modulator for a lowest one of the at least three radio frequency channels does not have a notch filter for filtering the second components of the modulated signal that extend beyond the predetermined frequency range at lower frequencies;

a signal combiner for combining a respective output signal from each of said plurality of consumer electronic video devices to generate a combined output signal; and

a single conductive path for distributing the combined output signal to a plurality of video receivers.

5. A radio frequency signal distribution network, said network comprising:

a plurality of consumer electronic video devices, each of said devices including circuitry configured to transmit a first video signal corresponding to a selected one of a plurality of radio frequency channels, the circuitry including a modulator configured to modulate said video signal such that the modulated video signal fails within one of a plurality of mutually exclusive predetermined frequency ranges, each mutually exclusive frequency range having a bandwidth of less than 6 megahertz and corresponding to a respective one of the plurality of radio frequency channels, and

a signal combiner for combining a respective output signal from each of said plurality of consumer electronic video devices to generate a combined output signal;

a single conductive path for distributing the combined output signal to a plurality of video receivers; and

at least one video display device coupled to the single conductive path for receiving the combined signal from said combiner.

6. A consumer electronic video device, said device comprising:

a plurality of video signal input ports, each of said ports configured to receive a respectively different one of a plurality of signals;

a plurality of modulators, each of said modulators coupled to a respective one of the video signal input ports for modulating a respective one of the plurality of signals to produce a plurality of modulated signals, whereby each of said modulated signals occupies a mutually exclusive radio frequency range;

a plurality of notch filters, each of said notch filters coupled to a respective one of said modulators, each of said notch filters being configured to receive a respective one of said plurality of modulated signals and to filter from said respective one of said plurality of modulated signals portions of said respective one of said plurality of modulated signals that may interfere with an adjacent radio frequency channel to produce a plurality of filtered signals, wherein the plurality of notch filters includes at least first and second notch filters coupled in series between said respective one of said modulators and said combiner, the first notch filter being configured to reduce, in amplitude, interfering signals corresponding to an adjacent one of said plurality of modulated signals occupying a frequency range less than the frequency range of the modulated signal produced by the respective one modulator, and the second notch filter being configured to reduce, in amplitude, interfering signals corresponding to a further adjacent one of said plurality of modulated signals occupying a frequency range higher than the frequency range of the modulated signal produced by the respective one modulator;

a combiner for receiving and combining said plurality of filtered signals from said plurality of notch filters to produce a combined output signal; and

an output port through which said output signal is transmitted.

7. A consumer electronic video device according to claim 6 wherein said consumer electronic device is selected from the group consisting of video devices, audio devices or data devices.

8. A consumer electronic video device according to claim 6 wherein each of said plurality of signals received by said plurality of video signal input ports is provided by a respective apparatus selected from the group consisting of video cassette recorders, digital video disc players, gaming units, satellite set top boxes and cable set top boxes.

10. A consumer electronic device according to claim 6, wherein:

(1) said plurality of modulators further comprises n modulators comprising;

(a) a first modulator configured to produce a first modulated signal occupying a lowest frequency range in the plurality of modulated signals, said lowest frequency range corresponding to a lowest channel;

(b) a last modulator configured to produce a last modulated signal occupying a highest frequency range in the plurality of modulated signals, said highest frequency range corresponding to a highest channel; and

(c) a second plurality of modulators numbering n−

2 modulators, each of said n modulators configured to produce one of n−

2 modulated signals occupying frequency ranges between said lowest frequency range and said highest frequency range, said n−

2 modulated signals corresponding to n−

2 channels between said lowest and highest channels; and

(2) said plurality of notch filters further comprises 2n−

2 notch filters comprising;

(a) a first notch filter coupled to said first modulator, said first notch filter configured to receive said first modulated signal and to filter from said first modulated signal portions of the first modulated signal which interfere with a next highest channel of said n−

2 channels;

(b) a last notch filter coupled to said last modulator, said last notch filter configured to receive said last modulated signal and to filter from said last modulated signal portions of the last modulated signal that interfere with a next lowest channel of said n−

2 channels; and

(c) a second plurality of notched filters comprising n pairs of notched filters, each of said n pairs of notched filters comprising further first and second notch filters coupled in series, said further first notch filter coupled to a respective one of said n−

2 modulators and configured to receive a respective one of said n−

2 modulated signals, said second notch filter coupled to said combiner.

11. A consumer electronic device according to claim 10 wherein said further first notch filter is configured to filter from said respective one of said n−

2 modulated signals portions of said respective one of said n−

2 modulated signals that interfere with a next lowest channel, and said further second notch filter is configured to filter from said respective one of said n−

2 modulated signals portions of said respective one of said n−

2 signals that interfere with a next higher channel.

9. A radio frequency device comprising:

first and second notch filters configured to receive a modulated input signal corresponding to a main radio frequency channel, and configured to reduce, in amplitude, portions of the modulated input signal in respective first and second guard bands between said main radio frequency channel and first and second respective radio frequency channels adjacent to said main radio frequency channel such that said modulated input signal is converted to a filtered modulated signal;

third and fourth notch filters configured to receive a second modulated input signal corresponding to the second radio frequency channel, and configured to reduce, in amplitude, portions of the second modulated input signal in the second guard band and in a third guard band between the second radio frequency channel and a third radio frequency channel adjacent to the second radio frequency channel to produce a second filtered modulated signal; and

a combiner for combining said main filtered modulated signal and said second filtered modulated signal.