System and method for wideband high current RF choke network

Abstract

A high current RF choke network comprising a high current RF choke combined with an all-pass T-bridge filter. The high current RF choke may be connected to a grounded capacitor in the serial branch of the all-pass filter. In this case the parasitic capacitance of the RF choke practically becomes an integral part of the all-pass filter capacitor. The added capacitance in parallel to the parasitic capacitance of the high current RF choke practically neutralizes the resonances of the high current RF choke and thus extends significantly the operating frequency range of the network. The operating frequencies bandwidth range of the high current RF choke network is extended from the legacy range of 5 MHz to 1 GHz up to an extended range of at least 5 MHz to 3 GHz.

Description

BACKGROUND OF THE INVENTION[0001]A radio-frequency (RF) choke, commonly used in cable-television (CATV) networks, allow passing through high alternating current (AC) of 10-20 A, 50-60 Hz, while keeping the impact on the RF transmission chain (such as CATV RF transmission chain) minimal. Such impact is defined by transmission and reflection losses in the RF frequency band of the network. The transmission and reflection losses should be kept substantially constant across the working frequency band of the network. In other words, the transmission and reflection losses should have substantially flat response curve. These response curves should ideally be kept substantially flat for any bandwidth extension within the desired working range of frequencies.[0002]CATV networks typically distribute RF signals in the legacy 5 MHz to 1 GHz range. Prior art high current RF chokes used for these networks typically resonate at frequencies just above 1 GHz. This phenomenon limits the operating freq...

AI Technical Summary

Benefits of technology

[0005]According to embodiments of the present invention, a wideband high current RF choke is disclosed WITH operating frequencies bandwidth range extended from the legacy range of 5 MHz to 1 GHz up to an extended range of at least 5 MHz to 3 GHz. A high current RF choke arrangement according to embodiments of the invention consists of high current RF choke of the types that is already in use in CATV networks, combined with an all-pass T-bridge type filter. An all-pass filter connected to the legacy RF choke may be designed to eliminate the negative effect of resonance frequencies in order to allow a substantially flat response curve for RF signals in the extended operating range.

Problems solved by technology

The design of such systems requires keeping some guard-band frequencies unusable and tuning of such diplexers is complicated and expensive.

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