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A compact in‐phase power divider with filtering response is presented in this study. Spiral resonators are meant to realise compact size and bandpass‐filtering response. To improve the frequency selectivity of the presented power divider, a source–load cross‐coupling is introduced by placing input and output coupling lines. An in‐phase power divider with passband‐filtering response has been designed, fabricated and measured. The measured return loss and insertion loss of the fabricated power divider are 22 and 1.3 dB at 2.45 GHz, respectively. The 3 dB operating bandwidth of the fabricated power divider is 175 MHz. The total area of the fabricated power divider is 0.15λg × 0.3λg. The measured results verify the predicted attractive features.

A novel compact power divider with good frequency response and wide stopband based on composite right-/left-handed (CRLH) transmission line is presented in this article. To provide bandpass-filtering frequency response, the bandpass filtering circuits is applied to this power divider using the CRLH resonators. The bandpass filtering circuit can generate two transmission zeros at the lower and upper stopband and have a wide upper stopband. Besides, the phase shift of the CRLH filter is tuned to be 90 for the sake of replacing the conventional quarter-wave length branch line in the power divider. Moreover, the capacitive coupling between the input and output of the resonator is used simultaneously to generate three additional transmission zeros beside the passband edges. Then, the frequency selectivity of the power divider is greatly improved. A resistor is placed at the center of the symmetric plane to produce good isolation between the two outputs. A filter-integrated power divider operating at 3.7 GHz is implemented. Good agreement between the simulated and measured results is observed.

A novel compact ultra‐wide band antenna with L‐shaped slot is presented. The printed antenna is fed by a microstrip feed line to achieve impedance matching for the SMA connector. The proposed antenna offers 118% bandwidth when printed on a substrate of dielectric constant 4.4 and has an overall dimension of 23.7 × 23.7 × 0.8 mm3. The simulated and measured reflection characteristics of the antenna with the variation of key‐parameters along with radiation patterns of the final antenna are presented and discussed. In addition, by decreasing the dimension of radiating patch, band‐notched properties in the lower wireless local area network (WLAN) (5.15–5.35 GHz) or higher WLAN (5.725–5.825 GHz) bands are achieved. With the compact size and broadband, this antenna is very suitable for using in a trade‐off which has to be taken account for a design of miniaturisation.