Increase patch antenna bandwidth
Hi,
Are you using microstrip? Basically, you can increase you substrate thickness in order to improve you bandwidth.
From an antenna theory viewpoint, the antenna size in relation to wavelength sets the achievable bandwidth. There's a theoretical limit for the maximal bandwidth respectively minimal Q that can't be exceeded. Increasing the substrate thickness will result in a larger patch size for the same center frequency.
Ok, thank you . Do you mean that if I increase my substrate thickness, my frequency will also be the same? No changes at all? Lately, I found that on internet if we can put an air layer of some thickness between substrate and ground plane it also can increase the bandwidth.
I didn't contradict your suggestion, I meaned that the patch with thicker substrate (or air layer) must be enlarged (nearer to λ/2 in air) for same center frequency and this will give the bandwidth increase in a first order.
Or if you see it the other way round, for a fixed patch size, there are limited options to increase the bandwidth.
yes i m using microstrip thanks a lot
It is great to see that you have done research before posting the question.
Try scrolling down to the bottom of the page.
is there any site or sources for CST Microstrip learning or can we find cst learning videos, it will be v.thankful
Hi, maybe this video will help you a little bit https://www.youtube.com/watch?v=lsxl9ryj2dc Good luck.
Hi..
Bandwidth BW=f0/Q, where f0 is the freq of resonance and Q is the Quality factor..
Q=2*pi*Energy stored/Energy dissipated per cycle..
Therefore one way to increase BW is to decrease Q, i.e. *either by decreasing stored energy, or by increasing losses.
a) Decreasing stored energy: i) By increasing substrate height and ii) by reducing dielectric constant (which you told you can't change). Both these methods increase the fringing and hence reduce the energy stored in microstrip resonator.. However careful!! Increasing substrate height can excite unwanted surface waves.
b)Increasing Losses: i) By introducing losses in dielectrics (Which you told you won't alter) ii) By introducing Chip resistor.. However, introducing chip resistor and thus introducing losses reduces the gain, which can be elevated using superstrates.
c) Using multi-mode techniques: Many resonant modes can be stagger-tuned together to have large BW..by i) having stacked elements ii) having coupled parasitic elements iii) or by introducing*slots which individually introduces resonances which can be near enough together to form a wider band.
You can refer:
a) Microstrip antennas (Garg et al.) *b) Compact and broadband microstrip antennas (Wong) c) Microstrip patch antennas (Lee, Luk)
Thanks
yes it was great but you should me in this.( Hi My final project is bandwidth improvement of patch antenna using cst microstrip i need yours help pls guide me , it will be very thankful)
Yes, this is your final year project and you should work on this topic, like other students have worked on their topics. There was very useful input above, which will help to solve the problem. Also see the other threads on this topic (bottom of page).
If you prefer the easy solution of copying what other have done earlier: click me.
Hi
How we can design the width and length of patch antenna and what about the ground of the patch antenna