In spite of numerous advantages of microstrip patch antennas it is difficult to achieve a better trade off between the gain, bandwidth, and more prominently the size of antennas. It is desired to reduce the size of wearable antenna so that its performance should not be affected by the bending effect and minimum deposition of electromagnetic field in the human body. The bending effect due to human body movements on the impedance matching of textile-based rectangular microstrip patch antenna is investigated and analyzed. In the literature different types of wearable antennas have been reported. presented a study on the necessity of wearable antennas for personal area networks (PAN), BAN, and ISM band applications.

These materials are cotton, liquid crystal polymer (LCP), fleece fabric, foam, Nomex, nylon, conducting ribbon, insulated wire, conducting paint, copper coated fabric, and so forth Hall et al. In practice, synthetic or natural materials are used as substrate to manufacture the textile or cloth-based wearable antennas. The wearable antenna should have features like light weight, conformal, need to be hidden, and it should not affect the health of user. The textile- or cloth-based wearable antenna should communicate the voice, data, or biotelemetry signals at high data rates. These systems are wearable computers flexible mobile phones personal digital assistant (PDA) devices public safety band systems sports activities body area networks (BAN) industrial, scientific, and medical (ISM) band WLAN Wi-Fi Wi-max Bluetooth HYPER LAN and so forth. Nowadays, handheld communication devices and body centric communication systems need high-gain compact antennas which should be an integral part of the wearer clothing. The bending effect on the performance of this antenna is experimentally verified. The simulated and measured results of the proposed antenna are found to be in good agreement. A prototype antenna has been fabricated and tested, and the measured results are presented in this paper. This leads to mismatch the impedance at WLAN frequency band hence, a metamaterial square SRR is embedded inside the slot.

The slots are cut in rectangular patch to reduce the bending effect. The electrical size of this antenna is 0. The proposed antenna resonates at 5.10 GHz with a bandwidth and gain of 97 MHz and 4.92 dBi, respectively. This paper presents an indigenous low-cost metamaterial embedded wearable rectangular microstrip patch antenna using polyester substrate for IEEE 802.11a WLAN applications.

Patch antenna matlab