In this paper, a multi-band compact H-shaped microstrip antenna is studied. The resonant modes of the H-shaped structure are analyzed using the concept of electric and magnetic walls at the planes of symmetry. A flexible design approach that allows the pre-selection of the resonant frequencies of the antenna is described. Approximate design equations and curves are introduced and validated by simulated and experimental results. An H-shaped antenna is designed to support modes with resonance at 2.2, 2.8, 3, and 5 GHz. It is shown that dual-, triple-, or quad-band operation is possible by the proper location of a coaxial feed. Such antennas are implemented on duroid dielectric substrate with
r  2.2 and h  1.57 mm. The designed antennas are simulated by IE3D software and a good agreement with experimental results is demonstrated