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An efficient approach is presented in this article, to reduce radar cross section (RCS) of a microstrip patch antenna, without affecting other radiation characteristics by the application of a novel hybrid metamaterial (MM) structure. The microstrip antenna is designed to operate at 4.2 GHz. Three different configurations of MM structures (ie, CB_1, CB_2, and hybrid) with splitted square and ring shaped two nonidentical MM cells are designed and critically analyzed in the range of 2‐18 GHz. A hybrid MM configuration is chosen for the design and implementation of low RCS antenna due to its exceptional performance as compared to CB_1 and CB_2. The hybrid MM is organized in chessboard configuration, comprises of splitted square and ring shaped MM unit cell. The results show that proposed antenna gives substantially out of band RCS reduction from 6 to 18 GHz and the proposed antenna has a lower RCS than the reference antenna. Proposed antenna attains wideband bandwidth around 7.4 GHz (ranging 2.0‐4.4 GHz, 7.8‐9.1 GHz, and 14.3‐18 GHz). The maximum reduction of −30.1 dBsm at 16.4 GHz is achieved in the hybrid MM structure impinged microstrip patch antenna. Finally, the fabrication and performance evaluation of MM loaded antenna is carried out. Moreover, measured results of the fabricated samples are closely matched with simulated results, which prove the effectiveness of the adopted approach for practical applications.

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The development and performance evaluation of a thin, broadband, and tunable radar wave absorber with reduced complexity is a strenuous task. This Letter reports the design, fabrication, and non‐destructive measurement of an active frequency selective surface (FSS) embedded tunable radar absorber. The proposed absorber design consists of periodically patterned, PIN diode mounted‐active transmissive/reflective FSS with a straightforward bias network. The tunable absorption characteristics are obtained over a wide frequency range by controlling the bias voltage of PIN diodes. The features of the proposed tunable absorber are demonstrated through non‐destructive free space, microwave measurement of a fabricated prototype. The measurement results show the achievement of a remarkable bandwidth of 3.0 GHz, which enables dynamic control of the absorption characteristics ranging from 8.2 to 12.4 GHz. Such an approach paves the way toward the realisation of smart materials and structures for electromagnetic wave manipulation.

The simultaneous achievement of multiband absorption, polarisation-insensitive, and angularly stable absorber is a difficult job. Therefore, in this article, an efficient single-layered absorber is designed, critically analysed, fabricated, and experimentally validated. The proposed model incorporates eight sectors loaded a circle inside the square. The four discrete absorption peaks are observed at 4.4 GHz, 6.0 GHz, 14.1 GHz, and 16.0 GHz manifesting absorption intensities of 94%, 84%, 82%, and 92%, respectively. Parametric studies have been also exercised to investigate the influence of discrete geometrical design variables on the proposed absorber. The proposed structure is symmetrical in geometry, consequence in polarisation-independent behaviour. The absorption mechanism is also explained by analysing the surface current, electric field, and magnetic field distributions. Besides, the complex electromagnetic parameters are extracted to realise the absorption phenomenon. Additionally, to validate the simulated results, an optimal sample is fabricated and the measured response is well-matched with simulated ones.