In the paper we present the proposal of broadband patch antenna with reduced transversal size. The broadband operation is obtained by means of application of thick substrate and electromagnetic coupling made of two slots. The nonresonant dimension of the antenna is reduced by using H-type slot instead of simple rectangular slot. The antenna has been designed and fabricated and 29% bandwidth for WFS<1.5 has been achieved. The broadband matching has been confirmed by the measurement of the reflection coefficient of fabricated antenna. However, the radiation pattern in E-plane shows some irregularities and needs additional research.