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An asymmetrical inductance tank (AIT) structure provides high quality factor in tank and harmonic noise frequency filtering (HNFF) technique shorts harmonic noises to ground. The VCO directly drives the on-chipped double balanced mixer to convert RF carrier to IF frequency through local oscillator. Further, output amplifier improves final power performance. This paper presents the design for a prototype 1.721 GHz LC VCO, mixer, and output amplifier that have been designed for low phase noise and high output power. The HNFF-VCO exhibited a phase noise of -133.96 dBc/Hz at 1 MHz offset and a tuning range of 261 MHz. While totally on-chipped downconverter shows a third-order input intercept point (IIP3) of 12.44 dBm, a third-order output intercept point (OIP3) of 21.44 dBm, an input P1dB of 3 dBm, an RF return loss of -31 dB, and an IF return loss of -26 dB. The RF-IF isolation is 57 dB. Also, this downconverter has a conversion gain of 8.9 dB through output amplifier. The totally on-chipped downconverter is 2.56 times 1.07 mm2 of chip area

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.

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/.