Novel ultra‐wideband coplanar‐waveguide bandpass filter with inductance‐loaded Y‐shaped resonators

Abstract

the S 11 complex conjugate impedance with a suitable source inductor. This results in the wideband and low-noise figure characteristics of LNA [6]. The third and fourth stages were designed to achieve the desired gain performance of whole circuit. The DC voltages were applied by DC probe, and RF choke were demonstrated by on-chip inductors. Figure 5 depicts the die photo of the Ka-band LNA, and the total chip area including the DC and RF pads is 0.6 Â 1 mm 2 . The transmission lines on this chip were using SCS-GCPW structure for low dielectric loss consideration at Ka-band application.The noise matching stages of LNA were biased at a supply voltage of 2 V together with a power consumption of 24 mW, and the gain-matching stages were biased at a supply voltage of 1 V, together with a power consumption of 16.5 mW. Figure 6 plots the measured results of the SCS-GCPW Ka-band LNA. It achieves an 24.5-dB gain at the peak gain frequency of 33 GHz and an average N.F. of 7.3 dB from 33 to 40 GHz. Because of the negative series feedback caused by the source inductive degeneration architecture of input stage, the LNA exhibited wideband 20-dB gain from 28 to 34 GHz. From the original design frequency of 30 GHz, it achieves input and output return losses of À6 and À10 dB, respectively. For further evaluation of the dynamic range behavior of the LNAs, the input 1-dB compression point and the output third-order intercept point (OIP3) were measured. Figure 7 shows that the measured third-order intermodulation (IM3) power was only À20 dBm at P 1 dB (À2 dBm), and OIP3 was 11.2 dBm at 33 GHz. Table 1 summarized the published Ka-band LNAs inclusive of this work. The comparison indicated that the SCS-GCPW LNA demonstrated a superior gain performance together with a low-noise figure at Ka-band. CONCLUSIONSA 33-GHz high-gain and low-noise amplifier has been successfully designed and implemented in a standard 0.18-lm CMOS technology and SCS-GCPW transmission lines. Due to the semicircle ground metal architecture, the lossy substrate induced signal loss and current crowding phenomenon were suppressed. Therefore, the dielectric loss of SCS-GCPW transmission lines was reduced to 0.075 Np/m. The measured results indicated that the low loss SCS-GCPW transmission lines were beneficial for improving the gain performance and reducing the transmission line induced noise of Ka-band amplifier circuits. ACKNOWLEDGMENTSThis work is financially supported by National Science Council of Taiwan, R.O.C (NSC-97-2221-E-182-048-MY3). The chip was fabricated by TSMC through the Chip Implementation Center (CIC) of Taiwan, R.O.C. ABSTRACT: A novel ultra-wideband (UWB) coplanar waveguide (CPW) bandpass filter (BPF) with the inductance-loaded Y-shaped

Compact ultra‐wideband notch‐band bandpass filters using multiple slotline resonators

“…Recently, ultra‐wideband (UWB: 3.1–10.6 GHz) devices and circuits have been developed greatly [1–12]. The UWB filter is one of the key passive components in the UWB systems, and the UWB bandpass filters (BPFs) have been developed based on various structures and design methodologies to meet the UWB systems [9–15]. Moreover, since the UWB radio system can cover very wide frequency band, and then may be interfered by the existing narrow‐band wireless local‐area network (WLAN) radio signals.…”