In this contribution, the design and analysis of an active multifunction biquad filter that provides five voltage-mode filtering configurations in the same core filtering circuit are presented. The design emphasizes using the commercially available ICs, LT1228, which are easy for off-the-shelf implementation and cheaper compared with the chip implementation. The proposed multifunction filter is realized from two commercial LT1228 ICs as the active function block, combined with five passive elements (three resistors and two capacitors) with three input voltage nodes and a single output voltage node. The following advantages are given for this design: (i) it provides high-pass (HP), low-pass (LP), band-stop (BS), band-pass (BP), and all-pass (AP) filtering functions; (ii) orthogonal and electronic tuning of the natural frequency ω 0 and bandwidth (the quality factor: Q); (iii) output voltage node of the proposed circuit is low impedance; (iv) passband voltage gain is controllable; and (v) matching condition and extra double gain voltage-mode amplifier are not required. The effect of the parasitic element in LT1228 on the filter performance is analyzed and included to strengthen the design idea. The PSpice simulation results using LT1228 with ±5 V and the experimental results tested from the hardware implementation are given to prove the validity of the designed multifunction filter.

We present the design of bandpass filter on the frequency of the QZSS satellite, by providing bandwidth at the cut-off frequency equally to the bandwidth of the QZSS L1 with selecting the response characteristic on Butterworth maximally flat amplitude. Bandpass filter design using frequency of the QZSS L1 with bandwidth is 24MHz. The design procedure involves two steps, the first step is to find the required order of the filter, which we use 3rd order, and the second step is to find the scale factor that must be applied to the normalized parameter values. The Band-Pass Butterworth filler is a combination between low pass and high pass. For the Butterworth filter, the value of a resistor that has been used are 50Ω. Then go to find the capacitor and inductor and by using PSpice as the tools for the simulation. The results of the output of bandpass filter at -3dB was between 1563 and 1587MHz. And was bandwidth around 24MHz. The combination of the lowpass filter and high pass filter is to perform as the bandpass filter. Therefore, there are two combinations also in designing bandpass filter. The aim of this combination is to have an influence on the performance of bandpass filter. As a conclusion, this designed filter on the frequency of QZSS L1 is to be useful by using bandpass filter.

This study focused on the design of the band-reject filter on the frequency of the Galileo satellite by providing bandwidth at the cut-off frequency equal to the bandwidth of the Galileo-E5a. The selecting of response characteristic is Butterworth's maximally flat, amplitude-frequency response of the band-reject filter. This poster shows the combination of the LPF and HPF to perform a band-reject filter. Therefore, there are two combinations also in designing for the band-reject filter. This combination aims to influence the performance of the band-reject filter. Band rejects filter design using the frequency of the Galileo-E5a with bandwidth is 25 MHz.using a Butterworth filter which is presented in this poster. The circuit is composed 3rd.order.Moreover, the combination between LPF and HPF is designed to act as a band-reject filter. As a  result, we can filter the frequency of Galileo-E5a by using the band-reject filter.

This research discusses about the combination of the LPF and HPF to perform band reject filter. Therefore, there are two combination also in designing band reject filter. The aim of this combination to get know is there have an influence on the performance of band reject filter was designed by using the frequency of the GalileoE6 with bandwidth 40 MHz. This filter is used a Butterworth filter which is presented in this study. These filter circuit is composed 4rd order. In addition to, the combination between LPF and HPF forming to a band reject filter is designed. As a result, the filter design on the frequency of Galileo-E6 is successfully used in band reject filter.