Introduction to Communications Circuitsmixers, voltage-controlled oscillators (VCOs), and power amplifiers. Synthesizers will be discussed in Chapter 10.References  Lee, T. H., The Design of CMOS Radio Frequency Integrated Circuits, 2nd ed., Cam-bridge, U.K.: Cambridge University Press, 2004. Razavi, B., RF Microelectronics, Upper Saddle River, NJ: Prentice-Hall, 1998. Crols, J., and M. Steyaert, CMOS Wireless Transceiver Design, Dordrecht, the Nether-lands: Kluwer Academic Publishers, 1997. Gray, P. R., et al., Analysis and Design of Analog Integrated Circuits, 4th ed., John Wiley & Sons, 2001. Johns, D. A., and K. Martin, Analog Integrated Circuit Design, New York: John Wiley & Sons, 1997. Gonzalez, G., Microwave Transistor Amplifiers Analysis and Design, 2nd ed., Upper Sad-dle River, NJ: Prentice-Hall, 1997. Pozar, D. M., Microwave Engineering, 2nd ed., New York: John Wiley & Sons, 1998.