Dual Port Antenna Combining Sensing and Communication Tasks for Cognitive Radio

Abstract

Abstract-Dynamic spectrum access has been proposed as the effective solution to overcome the spectrum scarcity issue, supported by cognitive radio technology. Sensing and communication functions are both the most important tasks in cognitive radio systems. In this paper, an antenna system combining sensing and communication tasks is proposed to be integrated into cognitive radio front-ends. The sensing task is performed by means of an ultra-wideband quasi-omnidirectional antenna. Whilst the communication task is ensured by using a narrowband antenna. Both antennas have been designed on the same layer of an FR4 substrate, for manufacturing cost constraint. Therefore, the isolation between them must take into consideration. The measured mutual coupling of less than -18 dB is achieved over the whole impedance bandwidth. The proposed sensing antenna covers a wide range frequency bands ranging from 2 to 5.5 GHz. While the communication antenna operates at 2.8 GHz, and by adding inductors to the antenna, the resonant frequency can be tuned from 2.6 to 2.7 GHz. The whole antenna system was designed, fabricated, and tested. Measurement and simulation results prove the feasibility of the proposed structure for cognitive radio applications.

Electronically reconfigurable filtenna for cognitive radios

“…It is interesting to note that the radiation pattern remains nearly constant in wideband and narrowband modes, which is an essential requirement for the CR systems when operating in crucial communication scenarios . Nevertheless, the obtained patterns are similar to those observed for antennas used for CR applications . The cross‐polarization level is less than −20 dB at broadside across the entire operating bandwidth for all the states.…”

Recent Developments of Reconfigurable Antennas for Current and Future Wireless Communication Systems

“…• to use a modified ground plane with embedded parasitic and slit structures and also slots along with active elements such as PIN diodes [51][52][53][54]. • to combine different antennas which can give narrowband or wideband operation and could be used in cognitive-ratio (CR) or MIMO mobile communications [55]. Some examples are described below.…”

“…There is an increasing demand in multi-service radios conforming to different spectrum standards for antennas switchable to single-band, multi-band, or wideband operation. This multi-function characteristic has become an important research area [47][48][49][50][51][52][53][54][55]. There are different antenna design methods which achieve this multimode function:…”

“…to combine different antennas which can give narrowband or wideband operation and could be used in cognitive-ratio (CR) or MIMO mobile communications [55].…”

A Hybrid Multi-Port Antenna System for Cognitive Radio

“…Some notable integrated CR antenna systems include coverage of: 3-11 GHz sensing band and four communicating sub-bands using a dimension of 68×54×0.79 mm 3 [14]; 2-5.5 GHz sensing band and 2.6-2.7 GHz communicating band using a dimension of 80×65×1.58 mm 3 [15]; 3.3-12 GHz sensing band and two communicating sub-bands using a dimension of 58.35 × 75.7 × 0.762 mm 3 [16]. Besides, a multiport antenna system of size 120 × 65 × 1.56 mm 3 reported in [17] uses two widebands for spectrum sensing and seven sub-bands for communication purpose.…”