Ruibing Dong

60-GHz-band low-loss on-chip band pass filter with patterned ground shields for millimeter wave CMOS SoC

This paper presents a design of an improved on-chip open loop resonator band pass filter (OLR-BPF) for 60 GHz millimeter-wave applications in 0.18 µm CMOS technology. The proposed on-chip BPF employs the folded open loop structure on patterned ground shields. The adoption of a folded structure for the OLR-BPF and utilization of two transmissions zero permits a compact size and high selectivity for the BPF. In addition, the patterned ground shields obviously slowed down the guided waves, which enables a further reduction of the physical length of the resonator and finally an improvement of the insertion loss of the BPF. By comparison between the electromagnetic (EM) simulations and measurement results, the proposed BPF has the center frequency of 59 GHz, insertion loss 2.77 dB, band width 14 GHz, return loss is less than 27.5 dB, and chip size 910×650 µm2 (including bonding pads).

Balun with passband characteristic for ultra-wideband (UWB) impulse radio transmitter

This paper presents on-chip balun with capacitors connected in series (BCCS) has three-order high pass frequency characteristic. It can be used to suppress the power spectral density (PSD) of UWB impulse radio (UWB-IR) signal within 0.96-1.61 GHz. With proper value of capacitor, BCCS has sharper cutoff edge than the balun without capacitor connected, which is desired for UWB-IR transmitter. The balun is fabricated in 0.18μm CMOS technology and tested. Its effectiveness to suppress the PSD of UWB-IR transmitter is demonstrated.

An UWB bandpass filter with large notch suppression

We present an ultra-wideband bandpass filter with −15dB suppression between 5.15–5.8GHz utilizing second order band elimination filter (BEF). The filter consists of a modified step impedance resonator (SIR) and two interdigital coupled line. Two parallel coupled stubs are attached to the SIR to create a second order BEF, which introduce a sharp and wide enough notch. HFSS was used to optimal the structure, and the measured result shown a good agreement with the simulated one. The 3dB bandwidth of the UWB Bandpass filter are between 3.1–4.8GHz and 6.1–10.2GHz