planar antennas, including microstrip, printed, metal-plate, ceramic chip, and dielectric resonator antennas, are flat and have a low profile. they have been widely used in mobile systems (900/1800 MHz), wireless local area networks (2.4/5.2/5.8 GHz), and ultra-wideband (3.1-10.6 GHz) communications. recent innovations in planar antenna designs for applications such as mobile phone antennas, base-station antennas, wlan mobile units (laptop, pda), access-point antennas, and uwb antennas are discussed. the design techniques for achieving high antenna performance are introduced. this tutorial presents the state-of-the-art modulated frequency synthesizers for wireless transmitter applications. it starts with an overview of modern rf transmitter architectures. several types of modulated frequency synthesizers with potential applications in wireless personal area networks are introduced. especially, a modulated frequency synthesizer using two-point delta-sigma modulation (tpdsm) is emphasized for its wideband characteristics. this architecture allows direct modulation of the signal using a frequency synthesizer, without mixers, for constant envelope modulation schemes like gfsk and gmsk.planar antennas, including microstrip, printed, metal-plate, ceramic chip, and dielectric resonator antennas, are flat and have a low profile. they have been widely used in mobile systems (900/1800 MHz), wireless local area networks (2.4/5.2/5.8 GHz), and ultra-wideband (3.1-10.6 GHz) communications. recent innovations in planar antenna designs for applications such as mobile phone antennas, base-station antennas, wlan mobile units (laptop, pda), access-point antennas, and uwb antennas are discussed. the design techniques for achieving high antenna performance are introduced. this tutorial presents the state-of-the-art modulated frequency synthesizers for wireless transmitter applications. it starts with an overview of modern rf transmitter architectures. several types of modulated frequency synthesizers with potential applications in wireless personal area networks are introduced. especially, a modulated frequency synthesizer using two-point delta-sigma modulation (tpdsm) is emphasized for its wideband characteristics. this architecture allows direct modulation of the signal using a frequency synthesizer, without mixers, for constant envelope modulation schemes like gfsk and gmsk.