How to enhance the bandwidth of PIFA
I have simulated a single band PIFA for GSM 900 applications. The center frequency is well coinciding with 925 MHz but the bandwidth is to small. |S11| is around -20 dB. How can I widen the bandwidth? I'm using Agilent ADS2005A for PIFA simulation.
Your guidance is appreciated in this regard...
As with any antenna, increase the (electrical) volume. So you can increase the distance between groundplane and patch as well as the patch width. If you use a dielectric, decrease dielectric constant; air is of course best. Also the wdith of the shorting pin influence on the bandwidth.
More advanced methods make use of slots in the patch, parasitic and multiple resonances. There are many papers on this.
Distance between the feed point and Sort point also influence the bandwidth and as jone mentioned gap between groundplane and radiator patch nothing but dielectric thickness also affects bandwidth.
For proper understanding of pifa better read below books
Planar Antennas for Wireless communication - Kin-Lu-Wong
Compact and Broad Band Microstrip Antennas - Kin-Lu-Wong
Both are available in this site.
regards,
balaguru.
Added after 46 minutes:
go thr below link
https://www.edaboard.com/viewtopic.php?t=276296
i don't have any lab sheet for this purpose. our lab assistant just asked to design pifa for gsm 900 and 1800 bands, one single-band and one dual-band. i have read a lot and designed some but the problem is widening the bandwidth. ADS is being introduced to us in this lab so designing in ADS is a must, otherwise i am relatively expert user of CST MWS and i'm acheiving best results there. and don't know how to give all these parameters like, thickness, etc in ADS.