Gary P. Kennedy

A Novel Harmonic Noise Frequency Filtering VCO for Optimizing Phase Noise

InGaP/GaAs HBT LC-VCOs designed with and without the proposed harmonic noise frequency filtering (HNFF) technique are presented here. To optimize phase noise, the HNFF technique is compared using noise frequency filtering capacitors. The HNFF-VCO produced ultra low phase noise performance. The tuning range of this VCO is 261 MHz with an output power of -10.25 dBm at 1.721 GHz carrier. Furthermore, the phase noise of this VCO -133.96 dBc/Hz at 1 MHz offset. The HNFF-VCO is designed with a total chip area of 0.9 - 0.9 mm2. Its phase noise performance is enhanced by 8.9 dBc at 1 MHz offset by comparison with a N-VCO without the HNFF technique

Design of an MMIC broadband mixer with high output power using InGaP/GaAs HBT technology

In this paper, an InGaP/GaAs HBT MMIC broadband mixer with high output power is designed within a total chip area of 2.3 /spl times/ 0.85 mm/sup 2/. The down-conversion mixer shows return loss of 20 dB and a conversion gain of -2.7 dB in the broadband frequency range of 400 MHz to 10 GHz. It also shows a third-order input intercept point (IIP3) of +22.5 dBm, a third-order output intercept point (OIP3) of +19.8 dBm, and an output-referred 1-dB compression point (P/sub 1dB,out/) of +10 dBm.

Circuit techniques to improve the linearity of an up-conversion double balanced mixer with an active balun using InGaP/GaAs HBT technology

This paper describes two circuit techniques to improve the linearity of an up-conversion double balanced mixer (DBM). These techniques are optimized for dual-band operation in PCS and IMT-2000 applications. Also, the integrated active balun is used at the RF port to produce a single-ended RF output signal. To improve the linearity of the mixer, the emitter degeneration resistors and the current injection resistors are used. The DBM with both resistors shows an improved IIP3 from -7.0 dBm to 6.5 dBm and P/sub 1dB/ increases from -15 dBm to -4 dBm. Furthermore, a DBM which uses only the emitter degeneration resistor has been fabricated using an InGaP/GaAs HBT process.

A high linearity InGaP/GaAs HBT up-conversion double balanced mixer with common base drive stage

A high linearity double balanced mixer has been developed using InGaP/GaAs HBT technology. Features of the design include a common base drive stage and a common collector output buffer amplifier. The up-conversion mixer shows an input-referred 1-dB compression point (P/sub 1dB, IN/) of 15 dBm and a third order input intercept point (IIP3) of 21.6 dBm. The chip size of the developed mixer is 1.17 mm /spl times/ 1 mm. The isolation of LO-RF and LO-IF in the up-conversion mixer shows 58.5 dB and 86.2 dB, respectively.

A comparative analysis of differential LC VCOs with different tank structures in InGaP/GaAs HBT technology

InGaP/GaAs HBT differential LC VCOs designed with low current consumption and low phase noise performance are presented here. To this end, the two types of oscillator are compared using symmetric and asymmetric inductors. The VCO with symmetric tank structure is 160 MHz of the output frequency range and -12.06 dBm of the output power at 1.66 GHz. Furthermore, the phase noise of this VCO is -73.9 dBc/Hz at 10 kHz and -113.9 dBc/Hz at 1 MHz offset frequencies. This VCO is designed within a total chip area of 0.9 /spl times/ 0.9 mm/sup 2/. Also, the VCO with asymmetric tank structure is 260 MHz of the output frequency range and -12.36 dBm of the output power at 1.46 GHz. Furthermore, the phase noise of this VCO is -83.3 dBc/Hz at 10kHz and -123.09 dBc/Hz at 1 MHz offset frequencies. This VCO is designed within a total chip area of 0.85 /spl times/ 0.9 mm/sup 2/.