Circular Dipole Antenna for Mode 1 UWB Radio With Integrated Balun Utilizing a Flex-Rigid Structure

Abstract

Abstract-A fully integrated dipole antenna with balun for ultra-wideband (UWB) radio utilizing a flexible and rigid printed circuit board is presented in this paper. The concept in this paper is to take advantage of the respective possibilities of the rigid and the flexible part. The balun utilizes broadside-coupled microstrips and is integrated in the rigid part of the printed circuit board, whereas the radiator is placed in the flexible part. The antenna with the balun covers the Mode 1 UWB frequencyband 3.1-4.8 GHz (with margin) at VSWR<2. Furthermore, good radiation characteristics and a linear phase response are observed with measurements.

Parallel Channels Using Frequency Multiplexing Techniques

“…It is seen in the simulated and measured results that the circular dipole antenna for the upper UWB band (6-10.6 GHz) has a wide impedance bandwidth (a VSWR<2.5 bandwidth from 5.5 to 11.0 GHz). A small shift in frequency is also seen in both graphs, which is likely due to the fact that the simulated phase velocity is lower than the actual one (Karlsson & Gong, 2009). Fig.…”

“…A balun is needed to convert the differential port of the dipole antenna to a single-ended port, i.e., to connect to a single-ended front-end. The backside of the rigid part (Metal 4) is completely covered with metal to make through-board ground vias possible, and to provide additional solderable ground-junctions for the SMA connector (Karlsson & Gong, 2009). Drilled vias with a diameter of 0.3 mm are used for grounding.…”

“…Drilled vias with a diameter of 0.3 mm are used for grounding. For a detailed study of the performance of the Mode 1 antenna, see (Karlsson & Gong, Oct. 2009). Antenna solutions for both the Mode 1 and the 6-9 GHz frequency bands was originally presented in (Karlsson et al, Sept. 2009).…”

“…However, some difference between simulation and measurement is seen, especially outside the Mode 1 UWB frequency-band. This is also due to the fact that the effect of the balun is not included in the radiation simulation (Karlsson & Gong, 2009). Fig.…”

Frequency Triplexer for Ultra-Wideband Systems (6–9 GHz)

“…Flexible materials have been used in wired interconnects, i.e., mainly in high speed interconnects in the Gbps domain [39]. Using the flex-rigid technology an antenna can easily be integrated in the flexible part of the printed circuit board while other components can be integrated in the rigid part [40]. One of the uniqueness's T with the design presented in this paper is that the triplexer is fully integrated in the "rigid part" of the flex-rigid printed circuit board using microstrips, resulting in a high performance and flexible solution but at low cost.…”