Radio frequency filter on basis of variable transconductance operational amplifier

Abstract

The invention discloses a radio frequency filter on the basis of a variable transconductance operational amplifier, which comprises a negative resistance matrix and an active LC (inductance capacitance) filter which are connected in parallel, wherein the the active LC filter is formed in a mode that an active inductance matrix is connected in parallel with a capacitance; an active inductance variation range of the active inductance matrix is configurated by a digital control signal provided by an external controller, and the active inductance matrix is controlled by an analog control signal provided by the external controller to continuously change in the currently selected active inductance variation range, so that the aim of continuously changing an active inductance value is fulfilled; and a negative resistance variation range of the negative resistance matrix is configurated by the digital control signal provided by the external controller, the negative resistance matrix is controlled by the analog control signal to continuously change in the negative resistance variation range, the loss of the active LC filter is counteracted, and the Q value of the active LC filter is ensured. After the radio frequency filter is adopted, the defects of low Q value and single working frequency range of the active filter are overcome. The radio frequency filter can work in the wide frequency band range. The Q value of the radio frequency filter is kept at a high level in the whole frequency band.

Description

technical field

[0001] The invention belongs to the radio frequency integrated circuit technology, in particular to a radio frequency filter based on a variable transconductance operational amplifier. Radio frequency filter is one of the key modules of Radio over Fiber (ROF) broadband wireless network, and also one of the key modules of traditional wireless networks, such as Wlan, GSM and other wireless communication networks. Background technique

[0002] Existing RF filters are divided into two categories: active and passive. Passive filters are mainly represented by LC filters, whose main features are high Q value, low noise, and no additional power supply, but it is difficult to integrate, especially in low frequency bands, so it cannot meet the miniaturization needs of modern communication systems; active The filter was first produced in 1938, but due to the limitations of the technology at that time, it was not widely used. In recent years, with the rapid development ...

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