PDF | First Page of the Article | ResearchGate, the professional network Design . of. Microwave Filters. by Ian Hunter gives a. T. good tutorial. Microwave Filters for Communication Systems: Fundamentals, Design, and Applications, Wiley, 2007. 3. Ian Hunter, Theory and Design of. microwave filter design remains an active research area till date and surely ..  Ian Hunter, ―Theory and design of microwave filters‖, IEE electromagnetic.
|Language:||English, Spanish, Dutch|
|Distribution:||Free* [*Registration Required]|
The book by Ian Hunter is quite good: theory and design of microwave filters post the pdf or any useful link to down load free. thank you very much >theory and. Ridge waveguides and passive microwave components. J. Helszajn “In his forward to Ian Hunter's book Leo Young writes: microwave filter design theories . IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. IEEE, Richard Parry, Senior Member, IEEE, Ian Hunter, Senior Member, IEEE.
EBG structures are compatible with standard planar microwave circuit technology due to its advantages like low cost, easy fabrication and miniaturized circuit.
To reduce filter size resonators are preferred most but sometimes they are unable to improve spurious response, so slow-wave EBG structures are proposed and implemented by to reduce size as well as to improve response of the filter .
Defected Ground Structures DGS are used to design filters by etching circular,triangular, rectangular holes and dumbbell shape holes in the ground plane to improve the performance of the filter . The design of band pass filter cascading fork resonator and EBG structure is proposed to reduce filter size with better performance .
In this paper, the challenge is to design the multi-band pass filter with a Mushroom-like EBG structure. The slit top truncated structures are compared with conventional mushroom-like EBG. The simulation results by using Ansoft HFSS software will show the curves of transmission characterisrics,s 21 of the filter. Theory The mushroom-like EBG structure behaves as a network of parallel resonant LC circuit, which acts as a network of a two-dimensional electric filter to block the flow of current.
It consists of a lattice of metal patches, connected to a solid metal sheet by vertical conducting vias. While interacting with electromagnetic waves, the electric charges are built up between ends of adjacent patch and the sheet between the top and bottom plate, which can be considered as a capacitance.
At the same time, the current flows around the path through the vias and the bottom plate, which results in inductive effect .
The mushroom-like EBG and its equivalent circuit is shown in figure 1 below. Thus, a short circuit between the microstrip line and the ground has been created. Design and simulation results of multi-band pass filter In this section the conventional mushroom-like EBG structure and Mushroom-like EBG structure with one, two and three slit tops are designed. The conventional mushroom-like EBG structure with above parameters is shown below.
Figure 4: Mushroom-like EBG structure with one slit-top Figure 5: Transmission characteristics of mushroom-like EBG structure with one slit-top As compare to conventional mushroom-like EBG the transmission characteristics with one slit-top shows dual band filter characteristics. Two bandgaps between frequencies 3. Figure 2: Conventional mushroom-like EBG structure The transmission characteristics of above designed structure shows one bandgap between frequencies 2.
This means that both model are accurate, and this do not happen so frequently in everyday life. Maybe I win a coffee from some sceptical readers which do not believe in Simulator at all. Going ahead in our simulation, we can try to abolish the lumped components present in the circuit and make the filter only with distributed ones.
Another step ahead is the removal of 27 nh inductor and use instead direct electromagnetic coupling of the two resonators. Correct coupling is reached easy, simply moving the resonators in closed proximity, till the coupling is optimal.
This is a very short distance, but remember that even the substrate thickness is thin again 0. This makes resonator longer, and if the circuit is operating at 1GHz or below dimensions are a concern.
The best way to reduce dimensions is to fold resonators many times, to reduce dimensions. The second simulation with copper metal and lossless dielectric makes the difference, since loss goes to 0.
Clearly the abnormal loss in the physical prototype is located in the dielectric of epoxyglass board. A subsequent run was made setting the tangent loss to 0. A second prototype was built using a TMM4 Roger laminate for microwave, with a loss of only The simulation gave a loss of 0.
Real world loss: consider that the loss of the physical prototype will be always higher than the simulation. You can correct the situation increasing the loss of dielectric and copper, but it is difficult to exactly manage it.
In the case of epoxy-glass board the divergence is sensational since epoxy is only characterised at 1MHz and at 1 GHz the loss increase 3 to 5 times. Current distribution: From electromagnetic simulation you can extract a lot of useful information, editing the loss parameters you can see where the main losses are located. Another very useful parameter is current distribution at different frequencies. Manufacturing a sample of the circuit we find correct the central frequency and the shape of the filter, but the loss was approximately 3.
As you can see out of resonance the current do not cross to the second resonator to the output, while in resonance the two resonator are crossed by an equal current minus the losses.
It is important to see that out of resonance the current in the first resonator is higher than the current in resonance. This is usually produced by stationary waves and must be accounted if the circuit is exited with high power. A good book is listed in Reference 8. Now we look at the various component that can be build directly into the PCB, in fig.
The circuit contain four resonators, in order to have a good rejection at out of band frequency, the passband is from 750 to 1000 MHz. The cutoff is enhanced at low frequencies, since the connection between resonators is capacitive and the response is of high-pass coupling type. On the bottom there are three capacitors: stub, rectangular and interleaved. Of the three inductor the most common is the square, because it requires less memory in the simulation then the spiral one.
If the interior of the inductor isn t connected to ground it requires a jumper to connect it to the rest of the circuit. The design parameters that are assigned a quantity such as geometry dimensions, material properties, boundary and excitation properties, can be varied.
The number of variations in parametric sweep setup is limited.
All variables must be defined to the nominal design before starting the parametric analysis. Results and Discussion: B. Eigen Mode Solution: General specifications and results obtained after simulation The Eigen mode solution solver in HFSS finds the Eigen of 3-element DR filter and 6-element DR filter design are modes or resonances of lossy as well as lossless structures.
Hence, it can be observed that 6- It can calculate the unloaded quality factor along with the element dielectric resonator filter with greater quality factor electric and magnetic field distributions at those resonant is more suitable to find application as output multiplexer in frequencies in the dielectric resonator and DR filter as satellite communication systems. The port, their excitation and radiation boundaries may not be defined. Also the frequency IV.
The interresonator coupling This research effort has become successful. It presents the between two dielectric resonators through coupling study, design and analysis of a Cylindrical Dielectric apertures can be observed from figure 12. All rights reserved by www. Matthaei, Leo Young and E. T Jones, Dielectric Resonator Filters.
Dielectric Resonator and filter obtain low loss November 1985. An investigation of the parametric studies on the resonator and filter parameters has also been presented. It possesses many variables for tuning and further advancement. We sincerely thank Mr.
Deshraj Shakya and Mr. Sovan Mohanty. Zaki, Tim G. Dolan and Ali E. Praveen Kumar, Vinu Thomas and K.