Heeseon Shin

Design and Analysis of a Cascode Bipolar Low-Noise Amplifier With Capacitive Shunt Feedback Under Power-Constraint

A cascode bipolar low-noise amplifier (LNA) with capacitive shunt feedback has been developed to present a solution for simultaneous noise and power match when the real part of the optimum source impedance is not 50 Ω in order to keep high current density under power constraint. The proposed LNA also has the capability for the simultaneous improvement of noise figure (NF) and linearity. In addition, we analyzed and verified that the second-order interaction, which affects the third-order nonlinearity, becomes less sensitive to the low-frequency input termination at higher bias currents. The possibility of removing the low-frequency LC trap is investigated based on this analysis. We also show that LNAs with smaller base and/or smaller emitter resistances require lower source impedance at low frequencies to improve linearity by the same amount. Finally, prudent layouts for improving the performance of the LNA are considered. Eleven design examples of the proposed LNA, which individually operate at 880, 1575, or 1960 MHz, are fabricated in a low-cost 0.35- μm SiGe BiCMOS process to verify the design and analysis experimentally. The fabricated LNAs have excellent performances, especially in NF. For example, the 880-MHz LNA has an NF of 0.9 dB, a power gain of 16 dB, and an IIP3 of +14 dBm with current consumption of 11 mA from a 2.8-V power supply.

A dual-b and RF front-end of direct conversion receiver for wireless CDMA cellular phones with GPS capability

A highly integrated direct conversion receiver for cellular code division multiple access (CDMA) and GPS applications is successfully developed using a 0.5-/spl mu/m SiGe BiCMOS technology. The receiver consists of two low-noise amplifiers (LNAs), a dual-band mixer, two voltage-controlled oscillators (VCOs), a local-oscillator signal generation block, and channel filters. The CDMA LNA achieves a noise figure of 1.3 dB, an input-referred third-order intercept point (IIP3) of 10.9 dBm, and a gain of 15.3 dB with a current consumption of 9.8 mA in the high-gain mode. The mixer for the CDMA mode achieves an uncalibrated input-referred second-order intercept point of 53.7 dBm, an IIP3 of 6.4 dBm, a noise figure of 7.2 dB and a voltage gain of 37.2 dB. The phase noise of the CDMA VCO is approximately -133 dBc/Hz at a 900-kHz offset from a 1.762-GHz operating frequency. It exceeds all the CDMA requirements when tested on a handset.

IP2 calibrator using common mode feedback circuitry

An IP2 calibration technique is developed using the common mode feedback circuitry in a direct-conversion receiver for wireless CDMA/PCS/GPS/FM applications. The IP2 calibrator is capable of providing a different CMFB gain to tune its common mode output impedance for each of the positive and negative mixer outputs. The method performs a 20-dB improvement in IIP2. The CDMA mixer achieves an uncalibrated IIP2 of 44 dBm, an IIP3 of 4 dBm, a noise figure of 6.5 dB and a voltage gain of 42.2 dB. The receiver RFIC is implemented in a 0.5 /spl mu/m SiGe BiCMOS process, and it operates from a 2.7 to 3.1 V single power supply. It exceeds all CDMA requirements when tested individually or on a handset.

An RF receiver for multi-band inter- and intra-band carrier aggregation

An RF receiver for carrier aggregation employing a low noise amplifier with a current reusing technique and a frequency-band switchable transformer is demonstrated in a 28nm LP CMOS technology. The proposed single-ended low-noise amplifier can support multiple-channel RF signals for both inter- and intra-band carrier aggregation with high performance and low DC current consumption. Moreover, a frequency-band switchable transformer is developed to realize a size-efficient receiver for handling three carrier components carrier aggregation. The receiver operates at frequency bands, ranging from 0.7 to 2.7 GHz. The receiver has conversion gain more than 70 dB and noise figure of less than 3.5 dB for all carrier aggregation combinations.

Design and Analysis of an Ultra-Wideband Automatic Self-Calibrating Upconverter in 65-nm CMOS

In this paper, an ultra-wideband (UWB) upconverter is proposed that has automatic self-calibrating circuits for the in-phase/quadrature mismatch correction and the local (LO) leakage suppression. The proposed self-calibrating circuits have been devised to have UWB functionality without help of the baseband processor. In addition, calibrating circuits do not need any additional analog-to-digital converter or sample-and-hold capacitors that are used to store and update the minimum power because the proposed calibrators find the solution from informations in current state. To verify the performance, the upconverter was applied to an UWB transmitter (Tx), operating from 3.1 to 4.8 GHz and from 6.3 to 9 GHz in 65-nm CMOS. The measured data shows UWB performance for the sideband rejection up to 9 GHz and the LO leakage suppression up to 5 GHz, respectively. The automatically calibrated Tx has error vector magnitude of lower than -20 dB, output 1-dB compression point of -6 dBm, LO leakage of lower than -43 dBm, and sideband suppression ratio of higher than 45 dBc with current consumption of 175 mA from a 1.2-V power supply for all supporting bands and time frequency codes defined in WiMedia UWB specifications.

An Ultra-wideband transmitter with automatic self-calibration of sideband rejection up to 9 GHz in 65nm CMOS

An Ultra-wideband (UWB) transmitter is proposed that can correct phase errors in quadrature local (LO) signals automatically without help of baseband processor (BBP), operating from 3 to 9 GHz in 65 nm CMOS. The measured tuning range for sideband rejection is 32.7 dB at 7.7 GHz and 13.6 dB at 8.7 GHz. The measured EVM is lower than −20 dB for all supporting bands and TFCs (Time frequency codes) that are prescribed by WiMedia alliance. The power consumption of the transmitter including LO path and PLLs is 210 mW from a 1.2 V supply.

A current-efficient wideband cellular RF receiver for multi-band inter- and intra-band carrier aggregation using 14nm FinFET CMOS

A wideband cellular RF receiver for multi-band carrier aggregation employing a current-efficient wideband low noise amplifier and a frequency-band switchable transformer is demonstrated in a 14nm FinFET CMOS technology. The proposed wideband low-noise amplifier can support multiple-channel RF signals for intra-band carrier aggregation with high performance and low DC current consumption. Moreover, the frequency-band switchable transformer is used to support a size-efficient receiver up to 5 carrier components carrier aggregation. The receiver operates at frequencies between 0.6 to 2.7 GHz. The receiver has conversion gain more than 62 dB and noise figure less than 5 dB at all carrier aggregation combinations.

A 65nm CMOS low-noise three band group WiMedia UWB receiver

A low-noise and high-gain ultra wideband (UWB) receiver was developed using a 65nm CMOS technology and a wafer-level fabricated package. In order to enhance the gain and noise figure over a wide frequency band, the resistive feedback amplifier and two cascode stages with the inductive load resonating at three different frequencies are employed. The fabricated UWB receiver showed a high gain of 72.6 dB ± 0.7 dB overall operating frequency range, and an average noise figure of 4.1 dB in 3168 to 4752 MHz, 4.3 dB in 6366 to 7920 MHz and 5.1 dB in 7392 to 8976 MHz frequency band, respectively. The noise figure at high frequency edge is lower than 6 dB. The measured sensitivities in three band groups meet all WiMedia PHY specifications.

A WiMedia UWB transmitter up to 9GHz in 65nm CMOS and Wafer-Level Fabricated Package

A 3.1–4.7GHz and 6.3–9GHz RF transmitter fabricated in a 65nm CMOS technology and packaged with a Wafer-level Fabricated Package (WFP) is presented. For high frequency and wideband performances, all the effects of package are considered and loopback paths with a power detector are implemented. A new structure of T/R switch is devised for the low noise performance of Rx and the high linearity of Tx. With these circuits, the transmitter features high linearity, low power consumption and small chip area meeting all the WiMedia PHY spec.

A single-chip CDMA-2000 zero-IF transceiver for band-class 4 with GPS support

A single-chip cdma-2000 zero-IF transceiver has been successfully developed for band-class 4 (Korean-PCS band) with an additional GPS signal receiving functionality. The receiver showed excellent noise and linearity performance (full- path NF=2dB, IIP3=-6dBm) with very low phase-noise VCO (- 132dBc/Hz@1.25MHz/fOSC=3.71G). The Tx-Rx isolation turned out to be good enough for the sensitivity and single-tone desensitization requirement of the CDMA-2000 system. The IC was implemented on a 0.35mum SiGe BiCMOS technology.