GB2513657A

GB2513657A - Amplifier device

Info

Publication number: GB2513657A
Application number: GB1308056.9A
Authority: GB
Inventors: Jan Ariesen
Original assignee: Technetix BV
Current assignee: Technetix BV
Priority date: 2013-05-03
Filing date: 2013-05-03
Publication date: 2014-11-05
Anticipated expiration: 2033-05-03
Also published as: GB201308056D0; GB2513657B

Abstract

If the level detector 76 senses the presence of upstream signals above a specified frequency, for example 65 MHz, it operates the switches 54 and 56 to select diplexer filters 46,46 or 48,48 suitable for bidirectional operation with a higherÂ frequency upstream signal. This self-adapting technique removes the need to replace the bidirectional amplifier 40 when network frequency bands are changed.

Description

Title: Amplifier device

Field of the invention

This invention relates to an amplifier device and in particular an amplifier for use in a distribution network such as a signal communication network.

Background to the invention

In a signal communication network, such as a broadband network or cable television network, signals sent from a signal provider to a dwelling or home need to be a amplified to ensure adequate signal quality for use with multiple end user devices such as modems, set-top boxes, radio and televisions. An in-home amplifier is used to amplify the signal passing from the provider to the user and if required can be used to amplify the upstream signal from user devices for return to the signal provider.

is In-home amplifiers are designed with specific signal frequencies in mind to ensure that signal bandwidth, noise ingress and other signal characteristics are kept within acceptable limits. Where an entire communications network has its signal frequencies altered, for example to allow an upgrade to a different data communication standard, then existing in-home amplifiers become redundant as they are not able to operate at the altered frequency ranges and so must be replaced.

Background to the invention

In accordance with one aspect of the present invention, there is provided an amplifier device comprising a first amplification path adapted to amplify signals within a first frequency range and a second amplification path adapted to amplify signals within a second frequency range wherein a detector means, such as a level detector, is operable to switch signals between the first and second amplification paths dependent on signal frequency. By having an amplifier device with different amplification paths for different ranges of frequency signals, the amplifier device can readily accommodate upgrades or alterations to new signal frequencies, for example where upgrade of a communications network, which may take place over some years, will ultimately involve switching to a second frequency band.

I

The amplifier device may further comprise one input for receiving signals from a signal supplier, such as a cable network television provider, and a plurality of outputs, typically connectable to different items of consumer equipment, wherein the detector means is arranged to detect the frequency of signals passing from the plurality of outputs to the input, i.e. for a broadband network detecting the frequency of upstream signals passing from a consumer to a headend.

Preferably each amplification path shares a common amplification means. The amplification mcans may bc in the form of separate amplification elements provided a for signals communicated in opposite directions and thus for example comprise one amplification unit for downstream signals and one amplification unit for upstream signals.

A first and second switch means may be disposed at either end of the first and second amplification paths, each switch means responsive to the detector means to complete either the first or second amplification path dependent on a detected signal frequency.

By sharing a common amplification means, duplication of components is avoided so providing cost savings and reducing space required.

Preferably the first amplification path is configured for signals with a downstream frequency range of 85 to 1200 MFIz or 85 to 1700 Ml-lz and preferably for upstream signals at or below 65MHz. The second amplification path is configured for upstream signals above 85MHz, typically those with a frequency range between 100 to 400MHz.

The detector means is preferably responsive to a frequency of upstream signals passing from a user to a service provider.

Preferably each amplification path includes filter means to separate upstream and downstream signals for amplification by respective upstream and downstream amplifier units. The filter means may be one or more diplex filters.

Additional switch means, typically switchable in response to a signal from the detector means, may be disposed between the filter means and the amplification means.

The invention will now be described, by way of example, and with reference to the accompanying drawings in which:

Figure 1 shows a prior art in-home amplifier;

Figure 2 shows a schematic diagram of an amplifier in accordance with the present invention. *I0

Description

Figure 1 shows a known in-home amplifier which is typically supplied as a complete device 10. Amplifier 10 has an input 12 and a plurality of outputs 14, 14', which for clarity are shown as two outputs although multiple outputs can be provided.

is Broadband communication signals from a network provider are received at input 12 and routed through a series of amplifier elements and filters to reach each output 14, 14'. Conversely, signals received at each output from consumer devices, for example when sending pay on demand signals back to a network provider, arc also filtered and amplified. If required, amplifier 10 can be passive for the return path of upstream signals passing from outputs 14, 14' to input 12 and onwards to a service provider.

Amplifier 10 comprises first and second diplex filters 16, 18 disposed either side of amplifier elements 20, 22, each filter providing one path for a combined signal and separate high pass and low pass paths for a filtered signal. A first signal path is provided for downstream signals passing from input 12 through high pass filter portion 26 of diplex filter 16 to reach downstream amplifier element 20 and then to high pass filter side 28 of diplex filter 18 where the amplified filtered signal is split at splitter 30 to supply a plurality of outputs 14, 14'. A return signal path is provided for upstream signals passing from outputs 14, 14' which arc combined at splitter 30 before passing through low pass filter portion 32 of diplex filter 18 to be amplified at upstream amplifier element 22. These amplified upstream signals then pass through low pass filter portion 34 of diplex filter 16 to reach input 12 before travelling upstream to reach ahcadcnd of the network.

Diplex filters 16, 18 are configured to operate for specific signal frequencies. If the signal frequencies of the network change, then amplifier 10 will no longer work and will need to be replaced in its entirety with an amplifier having differently configured s filters. For a network-wide change in frequency bands, every single amplifier used in-home will need to be changed which is expensive and time consuming.

To reduce the expense and time involved in switching in-home amplifiers, an amplifier in accordance with the present invention is provided. The inventive amplifier 40 of Figure 2 provides alternative signal amplification paths switchable dcpcndcnt on thc frcqucncy of signals dctcctcd. Amplifier 40 provides a first amplification path 42 and a second amplification path 44, each amplification path having different filter elements 46, 46', 48, 48' configured to be suitable lbr different signal frequencies but sharing common amplification elements 50, 52 lbr upstream is and downstream signals.

The two amplification paths 42, 44 are separated by means of switches 54, 56 disposed in the combined signal paths from input 60 or tap 62 respectively. Tap 62 combines upstream signals from a plurality of outputs 64,64' (of which only two are shown for clarity).

Each filter element 46, 46', 48, 48' is a diplex filter comprising a high pass filter portion and a low pass filter portion so as to ffltcr upstream and downstream signals passing along amplification paths 42,44.

To ensure each amplification path 42, 44 can use common amplifier elements, additional switches 66,68,70 and 72 are disposed between filter elements 46,46', 48, 48' and amplification elements 50, 52. Each switch 54, 56, 66, 68, 70, 72 is in communication with level detector 76 which, by means of tap 78, receives a small portion of the signal passing between tap 62 and switch 56. Detector 76 assesses signal frequency and alters the switched position of switches 54, 56, 66, 68, 70, 72 dependent on the detected frequency to complete either amplification path 42 or amplification path 44.

Typically amplifier 40 is supplied with switches set to complete one amplification path 42 configured to be suitable for upstream signals up to 65MHz and downstream signals from 85MHz. The other amplification path is configured with appropriate diplex fihers to be suitable for another upstream frequency that it is envisaged to use in the future. Level detector 76 detects frequencies higher than the low pass fiher frequency of path 42. When level detector 76 detects upstream signals above a specified frequency, typically 65MHz, then it automatically operates switches 54, 56, 66, 68, 70, 72 to break contacts for path 42 and to complete path 44. The amplifier io can now be used with a differently configured amplification path, with differently configured filters, for both downstream and upstream traffic.

Often changes to network frequency bands are decided many years in advance of is switchover and the present invention allows in-home amplifiers to be friture-proofed ready for a change in frequency of networks, particularly for changes in upstream frequencies such as with the forthcoming Doesis 3.1, without losing bandwidth.

Filters more suited to different frequency signals can be provided within each amplification path, each amplification path only used as and when the frequency is detected for which their filters are configured. This avoids swapping the entire amplifier when a new frequency regime comes in and makes it casier to upgrade the upstream capabilities of the amplifier to higher frequencies like 200, 300 or even 400MHz. One can install amplifiers with the dual switchablc path option for some time in advance of the change allowing fewer amplifiers to be replaced when switchover occurs.

Claims

Claims 1. An amplifier device comprising a first amplification path adapted to amplify signals within a first frequency range and a second amplification path adapted to ampli' signals within a secoild frequency range, wherein a detector means is operable to switch signals between the first and second amplification paths dependent on signal frequency.
2. An amplifier device according to claim 1, further comprising one input for receiving signals from a signal supplier and a plurality of outputs, whercin the a detector means is arranged to detect the frequency of signals passing from the plurality of outputs to the input.
3. An amplifier device according to claim 1 or claim 2, wherein each amplification path shares a common amplification means.
4. An amplifier dcvicc according to any of the preceding claims, whcrein first and second switch means are disposed at either end of the first and second amplification paths, each switch means responsive to the detector means to complete either the fir st or the second amplification path dependent on a detected signal frequency.
5. An amplifier deyice according to any of the preceding claims, wherein the first amplification path is configurcd for upstrcam signals with a frequency below 65MHz.
6. An amplifier device according to any of the preceding claims, wherein the second amplification path is configured for upstream signals above 85MHz.
7. An amplifier device according to any of the preceding claims, wherein the dctcctor mcans is responsive to a frcqucncy of upstrcam sign&s.
8. An amplifier device according to any of the preceding claims, wherein each amplification path includes filter means to separate upstream and downstream signals for amplification by respective upstream and downstream amplifier units.
9. An amplifier device according to any of claims 4 to 8, wherein additional switch means are disposed between the filter means and the amplification means.s
10. An amplifier device substantially as herein described with reference to and as illustrated in the accompanying drawings.