Modified H-shaped microstrip antenna configurations are introduced. Additional stubs or etching slots can be properly used to tune the desired band and leave little effect on others. Using the proposed approach, some modes can be tuned over 20% frequency range. The technique improves the flexibility in the design approach that allows the pre-selection of the resonant frequencies of the antenna. The approach is validated by the design of different modified H-shaped antennas for operation in quad band. The designed antennas are simulated by IE3D software. Good agreement with experimental results is demonstrated