System Embedded Antenna for Portable TVWS Cognitive Radio Transceiver

For a wireless device with an internal antenna that is of similar size as its system circuit, for example, a portable TV white spaces (TVWS) cognitive radio transceiver, arranging the antenna and the system circuit together in a compact space without affecting antenna radiation is a big issue. In this letter, we propose a design methodology using the system circuit itself as the antenna, namely the system embedded antenna (SEA). Radio frequency (RF) chokes are used to segment and shape the system board in terms of the requirements of the antenna for efficient RF radiation. In the baseband, the circuit function has no change. The SEA was fabricated, measured, and compared to the original antenna without system circuit. The performance of the SEA transceiver was compared to the transceiver having a separated standard 2-dBi antenna in an indoor environment. The measurement results show that the SEA has similar performance to its original antenna. The SEA transceiver´s performance is comparable to the separated transceiver and antenna. Using this design methodology, the total size of the device can be reduced significantly. More importantly, the antenna radiation pattern is not affected by the system circuit because there are no other circuit parts besides the SEA.