The design and analysis of a low-power high-frequency CMOS sinusoidal quadrature oscillator is presented through the use of two 2nd-order low-pass current-mirror (CM)- based filters, a 1st-order CM low-pass filter and a CM bilinear transfer function. The technique is relatively simple based on (i) inherent time constants of current mirrors, i.e. the internal capacitances and the transconductance of a diode-connected NMOS, and (ii) a simple negative resistance RN formed by a load resistor RL of a current mirror. Neither external capacitances nor inductances are required. The oscillation frequency (f0) is 1.9 GHz and is current-tunable over a range of 370 MHz or 21.6%. The power consumption is at approximately 0.45 mW. The amplitude matching and the quadrature phase matching are better than 0.05 dB and 0.15o°, respectively. Total harmonic distortions (THD) are less than 0.3%. At 2 MHz offset from the 1.9 GHz, the carrier to noise ratio (CNR) is 90.01 dBc/Hz, whilst the figure of merit called a normalized carrier-to-noise ratio (CNRnorm) is 153.03 dBc/Hz. The ratio of the oscillation frequency (f0) to the unity-gain frequency (fT) of a transistor is 0.25. The variations of components between -1.5% and 1.5% indicates that the oscillation frequency is varied in the range between 1.8 GHz to 1.9 GHz, whilst the variations of temperature between 20 oºC and 100 oºC indicates that the oscillation frequency is downed from 1.9 GHz to 1.7 GHz. Comparisons to other approaches are also included.