Q-Band Compact Driver and Power Amplifier MMICs Matched by ?-type Low-Pass Filter Using Lumped Elements

According to the characteristics of ultrasonic guided wave inspection, An exciting power, used for exciting ultrasonic guided waves in pipeline is designed based on DDS and FPGA. The excitation source consists of FPGA, D/A conversion circuit, a low-pass filter circuit and power amplifier circuit. Constructing DDS based on FPGA as the controller and signal generator. Filter circuit and power amplifier circuit are designed in this paper. The experiment results show that the excitation source can have high voltage and high frequency output capability, and can generate desired signal type with a good accuracy to fit the requirements in practice. It can be conveniently used for pipeline ultrasonic guided wave detection.

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Analysis and Design of RF Filters with Lumped and Distributed Elements

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.b1009.0782s519 ◽

2019 ◽

Vol 8 (2S5) ◽

pp. 38-42

Keyword(s):

Short Circuit ◽

Rf Filters ◽

Pass Filter ◽

Low Pass Filter ◽

Analysis And Design ◽

Lumped Element ◽

Electronic Filter ◽

Low Pass ◽

Lumped Elements ◽

Distributed Elements

Radio frequency (RF) and microwave filters characterize a class of electronic filter, intended to function on signals in the frequency range between megahertz to gigahertz. A Lumped element RF filters is a passive device whose size across any dimension is much smaller than the operating wavelength so that there is minimal change in phase of waveform between the input and output connections. RF filters can also be designed using distributed elements in which all the inductors and the capacitors are replaced by the open and short circuit stubs. This paper concentrates on an analysis and design of low pass filter with the help of only lumped elements and a high pass filter with both lumped and distributed elements.

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Tunable Lowpass Filter with RF MEMS Capacitance and Transmission Line

Active and Passive Electronic Components ◽

10.1155/2012/502465 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5

Author(s):

Shimul C. Saha ◽

Ulrik Hanke ◽

Håkon Sagberg ◽

Tor A. Fjeldly ◽

Trond Sæther

Keyword(s):

Transmission Lines ◽

Parallel Plate ◽

Rf Mems ◽

Cutoff Frequency ◽

Lowpass Filter ◽

Pass Filter ◽

Low Pass Filter ◽

Measurement Results ◽

Low Pass ◽

Lumped Elements

We have presented an RF MEMS tuneable lowpass filter. Both distributed transmission lines and RF MEMS capacitances were used to replace the lumped elements. The use of RF MEMS capacitances gives the flexibility of tuning the cutoff frequency of the lowpass filter. We have designed a low-pass filter at 9–12 GHz cutoff frequency using the theory of stepped impedance transmission lines. A prototype of the filter has been fabricated using parallel plate capacitances. The variable shunt capacitances are formed by a combination of a number of parallel plate RF MEMS capacitances. The cutoff frequency is tuned from C to X band by actuating different combinations of parallel capacitive bridges. The measurement results agree well with the simulation result.

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