This work reports a systematic design of 5-pole and 7-pole low-pass filter using defected ground structures for wireless communication system. The cut-off frequency 5GHz of the LPF has been selected to cover all the wireless communication bands (PCS-1900, UMTS, IMT-2000, ISM, Bluetooth, RFID, WLAN, and WiMAX bands). The sharpness of cut-off improves significantly from 8.3 to 19.2 dB/GHz, 20 dB rejection from 7.1 to 11.6 GHz and the 30 dB rejection bandwidth increases from 2.5 to 5.9 GHz with increase in the order of filter from 5-pole to 7-pole.
- Defected ground structure
- Low-pass filter