Theory for Pseudo-Butterworth Filter Response and Its Application to Bandwidth Tuning

Nam, Seunggoo,Lee, Boyoung,Lee, Juseop Professional Technical Group on Microwace Theory a 2017 IEEE Transactions on Microwave Theory and Techniqu Vol. No.

<P>This paper presents a new class of filter responses called pseudo-Butterworth filter response. A detailed mathematical analysis on the pseudo-Butterworth response has been carried out. In addition, the comparison between the typical complete Butterworth response and the new pseudo-Butterworth response is provided. The theory for the pseudo-Butterworth filter response indicates that bandwidth tuning maintaining excellent return loss performance can be executed adjusting not all coupling structures of a filter. As an example, a bandwidth tuning method for a second-order filter is presented. For verifying the presented bandwidth tuning theory, a second-order substrateintegrated waveguide (SIW) resonator filter has been designed, fabricated, and measured. As an example of applications to higher order filters, a theory for the fourth-order pseudo-Butterworth responses and a bandwidth tuning method for the fourth-order filters have been developed. A fourth-order filter has also been fabricated and measured for verifying the presented bandwidth tuning technique.</P>

A 5-GHz WLAN RF CMOS Power Amplifier With a Parallel-Cascoded Configuration and an Active Feedback Linearizer

Kang, Seunghoon,Baek, Donghyun,Hong, Songcheol Professional Technical Group on Microwace Theory a 2017 IEEE Transactions on Microwave Theory and Techniqu Vol. No.

<P>This paper presents a highly linear cascode power amplifier (PA) for 5-GHz 802.11ac (wireless local area network) WLAN applications, which is fabricated with a 0.13-mu m standard RF CMOS process. A parallel-cascoded configuration is proposed to cancel out third and fifth intermodulation distortions and third harmonic distortion (HD) due to drain-source current nonlinearity. This also reduces distortions due to drain-source and gate-source nonlinear capacitances at both common source (CS) and common gate (CG) stages. The configuration allows the amplifier linear characteristics to be robust against gate node voltage variations of CG transistors compared to previous multigated transistor linearization methods, because the CG transistors always remain in the saturation region and the nonlinearities of capacitances associated with CG transistors cancel each other under a wide range of output powers. In addition, an active feedback linearizer is applied to improve AM-AM and the power-added efficiency (PAE) at high output powers. At 5.15 GHz, the proposed PA is tested with a 256-quadrature amplitude modulation WLAN 802.11ac signal source without digital predistortions. The output powers satisfying the stringent linearity, a -35-dB error vector magnitude, are 17.8, 17.3, and 15.6 dBm with 11.5%, 10.4%, and 7.5% PAEs at 20, 40, and 80 MHz, respectively.</P>

A 5.8-GHz DSRC Transceiver With a 10-<tex> $\mu{\hbox {A}}$</tex> Interference-Aware Wake-Up Receiver for the Chinese ETCS

Jeongki Choi,In-Young Lee,Kanghyuk Lee,Seok-Oh Yun,Joomyoung Kim,Jinho Ko,Giwan Yoon,Sang-Gug Lee Professional Technical Group on Microwace Theory a 2014 IEEE Transactions on Microwave Theory and Techniqu Vol. No.

<P>This paper presents a fully integrated 5.8-GHz dedicated short-range communication transceiver with a 10- μA interference-aware wake-up receiver (WuRx) for Chinese electronic toll collection system terminals that can operate with a low standby and operating current consumption. To reduce the current consumption, a high-gain RF envelope detector using a voltage-boosting method is proposed for both the WuRx and receiver (Rx) while the proposed high-power ASK modulator extends output dynamic range in low power consumption. Additionally, a delay-based bandpass filter is adopted in the WuRx to filter out interference from automotive applications, thus increasing the battery lifetime by reducing the probability of a false wake-up. The proposed transceiver is fabricated using 0.13- μm CMOS technology with a chip size of 2.8 mm<SUP>2</SUP> for the target frequency range of 5.8 GHz. The measured results demonstrate sensitivities of -44 and -61 dBm for the WuRx and Rx, dissipating currents of 10 μA and 19 mA from 3.3-V supply voltage, respectively. The transmitter exhibits a normal output power of +5 dBm at an operating current of 46 mA.</P>

A Low-Voltage, Low-Power, and Low-Noise UWB Mixer Using Bulk-Injection and Switched Biasing Techniques

Myoung-Gyun Kim,Hee-Woo An,Yun-Mo Kang,Ji-Young Lee,Tae-Yeoul Yun Professional Technical Group on Microwace Theory a 2012 IEEE Transactions on Microwave Theory and Techniqu Vol. No.

<P>This paper presents a low-voltage, low-power, low-noise, and ultra-wideband (UWB) mixer using bulk-injection and switched biasing techniques. The bulk-injection technique is implemented for a low supply voltage, thus resulting in low power consumption. This technique also allows for a flat conversion gain over a wide range of frequencies covering the full UWB band; this is a result of the integration of the RF transconductance stage and the local oscillator switching stage into a single transistor that is able to eliminate parasitic effects. Moreover, since the bulk-injection transistors of the mixer are designed to operate in the subthreshold region, current dissipation is reduced. A switched biasing technique for the tail current source, in place of static biasing, is adopted to reduce noise. The effects of modulated input signals, such as AM and FM, are simulated and measured to demonstrate the robustness of the switched biasing technique. The proposed mixer offers a measured conversion gain from 7.6 to 9.9 dB, a noise figure from 11.7 to 13.9 dB, and input third-order intercept point from - 10 to - 15.5 dBm, over 2.4 to 11.9 GHz, while consuming only 0.88 mW from a 0.8-V supply voltage. The chip size including the test pads is 0.62×0.58 mm<SUP>2</SUP> using a 0.18-μm RF CMOS process.</P>

A Multiband Reconfigurable Power Amplifier for UMTS Handset Applications

Unha Kim,Sungyoon Kang,Jungrin Woo,Youngwoo Kwon,Junghyun Kim Professional Technical Group on Microwace Theory a 2012 IEEE Transactions on Microwave Theory and Techniqu Vol. No.

<P>A new practical reconfigurable output network for a multiband reconfigurable power amplifier (PA) is proposed for universal mobile telecommunications system (UMTS) handset applications. The proposed reconfigurable network can reconfigure the output power and the output path, as well as the frequency. It consists of a power-reconfigurable network, a frequency-reconfigurable network, and a path-selection network. In this paper, its reconfiguration principle is described to extract key design parameters for the reconfigurable PA implementation. To demonstrate the performance of the proposed structure, a 5 mm × 6 mm multiband reconfigurable PA module is developed for UMTS high- and low-frequency band application. The fabricated PA module can cover any three bands out of five popular high- and low-frequency UMTS bands. To enhance the efficiency during low output power operation, the authors' stage-bypass technique is also employed. The fabricated PA module showed adjacent channel leakage ratios better than -39 dBc up to the rated linear output power and power-added efficiencies of higher than 39% at <I>P</I><SUB>out</SUB>=28 dBm over all the UMTS frequency bands. Efficiency degradation was limited to less than 2% compared to the single-band PA. Measured RF performance of the reconfigurable PA validates the usefulness of the proposed reconfigurable structure for multiband UMTS applications.</P>

300-GHz InP HBT Oscillators Based on Common-Base Cross-Coupled Topology

Jongwon Yun,Daekeun Yoon,Hyunchul Kim,Jae-Sung Rieh Professional Technical Group on Microwace Theory a 2014 IEEE Transactions on Microwave Theory and Techniqu Vol. No.

<P>Two fundamental-mode oscillators operating around 300 GHz, a fixed-frequency oscillator and a voltage-controlled oscillator (VCO), have been developed in this work based on a 250-nm InP heterojunction bipolar transistor (HBT) technology. Both oscillators adopted the common-base configuration for the cross-coupled oscillator core, providing higher oscillation frequency compared to the conventional common-emitter cross-coupled topology. The fabricated fixed-frequency oscillator and the VCO exhibited oscillation frequency of 305.8 GHz and 298.1-316.1 GHz (18-GHz tuning range) at dc power dissipation of 87.4 and 88.1 mW, respectively. The phase noise of the fixed-frequency oscillator was measured to be -116.5 dBc/Hz at 10 MHz offset. The peak output power of 5.3 dBm (3.8% dc-to-RF efficiency) and 4.7 dBm (3.2% dc-to-RF efficiency) were respectively achieved for the two oscillators, which are the highest reported power for a transistor-based single oscillator beyond 200 GHz.</P>

A 220–320-GHz Vector-Sum Phase Shifter Using Single Gilbert-Cell Structure With Lossy Output Matching

Younghwan Kim,Sooyeon Kim,Iljin Lee,Urteaga, Miguel,Sanggeun Jeon Professional Technical Group on Microwace Theory a 2015 IEEE Transactions on Microwave Theory and Techniqu Vol. No.

<P>This paper presents a wideband vector-sum phase shifter (VSPS) that operates over the entire WR-3 band (220-320 GHz). Compared to conventional VSPSs with double Gilbert cells, the proposed phase shifter employs a single Gilbert-cell structure for vector modulation. This reduces the output current combining ratio from 8:2 to 4:2, and boosts the impedance at the combining node, thus facilitating wideband output matching at upper millimeter-wave and terahertz bands. The simplified structure leads to a reduction in dc power consumption and chip area without sacrificing the 360 <SUP>°</SUP> phase-shifting property. Lossy matching is applied at the Gilbert-cell output to further increase bandwidth and stability at the expense of relatively high loss. The phase shifter is implemented using a 250-nm InP DHBT technology that provides f T and f max exceeding 370 and 650 GHz, respectively. The measurements exhibit a wideband phase shift with continuous 360 <SUP>°</SUP> coverage and average insertion loss ranging from 11.8 to 15.6 dB for the entire WR-3 band. The root mean square amplitude and phase error among different phase states are less than 1.2 dB and 10.2 <SUP>°</SUP>, respectively. The input-referred 1-dB compression is measured at 0.7 dBm on average. The dc power consumption is 21.8-42.0 mW at different phase states.</P>

Bandwidth Tuning of Resonator Filter Using Reduced Number of Tunable Coupling Structures

Lee, Boyoung,Nam, Seunggoo,Lee, Juseop Professional Technical Group on Microwace Theory a 2019 IEEE transactions on microwave theory and techniqu Vol.67 No.4

<P>This paper presents a new bandwidth tuning theory for Butterworth-response resonator filters. The presented theory shows that the bandwidth of odd-order Butterworth filters can be varied by adjusting only two interresonator coupling structures while maintaining a perfect impedance matching at the center frequency. In other words, this paper presents an analytic approach to reduce the number of tunable coupling structures when designing a bandwidth-tunable resonator filter. Theories for third- and fifth-order direct-coupled filters are discussed in detail, and it is shown that only two interresonator coupling structures are required to be tunable. In addition, for verifying the new bandwidth tuning method, a fifth-order cylindrical cavity filter has been designed, fabricated, and measured. The fabricated filter has an 11:1 bandwidth tuning range.</P>

An Extraction of Two-Port Noise Parameters From Measured Noise Powers Using an Extended Six-Port Network

Ahmed, Abdul-Rahman,Kyung-Whan Yeom Professional Technical Group on Microwace Theory a 2014 IEEE Transactions on Microwave Theory and Techniqu Vol. No.

<P>In this paper, we present a formulation for extracting the noise wave correlation matrix of a linear two-port device-under-test (DUT) from measured noise powers using a designed six-port network. The noise powers are measured using a conventional noise figure analyzer. The extracted noise wave correlation matrix can then be converted into conventional two-port noise parameters. The proposed measurement equipment is very simple and leads to a very low cost. The proposed method is experimentally verified through measurements of various DUT samples.</P>

A Stacked-FET Linear SOI CMOS Cellular Antenna Switch With an Extremely Low-Power Biasing Strategy

Donggu Im,Bum-Kyum Kim,Do-Kyung Im,Kwyro Lee Professional Technical Group on Microwace Theory a 2015 IEEE Transactions on Microwave Theory and Techniqu Vol. No.

<P>A stacked field-effect transistor (FET) linear cellular antenna switch adopting a transistor layout with odd-symmetrical drain-source metal wiring and an extremely low-power biasing strategy has been implemented in silicon-on-insulator CMOS technology. A multi-fingered switch-FET device with odd-symmetrical drain-source metal wiring is adopted herein to improve the insertion loss (IL) and isolation of the antenna switch by minimizing the product of the on-resistance and off-capacitance. To remove the spurious emission and digital switching noise problems from the antenna switch driver circuits, an extremely low-power biasing scheme driven by only positive bias voltage has been devised. The proposed antenna switch that employs the new biasing scheme shows almost the same power-handling capability and harmonic distortion as a conventional version based on a negative biasing scheme, while greatly reducing long start-up time and wasteful active current consumption in a stand-by mode of the conventional antenna switch driver circuits. The implemented single-pole four-throw antenna switch is perfectly capable of handling a high power signal up to +35 dBm with suitably low IL of less than 1 dB, and shows second- and third-order harmonic distortion of less than -45 dBm when a 1-GHz RF signal with a power of +35 dBm and a 2-GHz RF signal with a power of +33 dBm are applied. The proposed antenna switch consumes almost no static power.</P>