Low profile vehicular antenna for wideband high frequency communications

This paper discusses the top-loading as a technique to miniaturize a monopole antenna to be primarily used for the 10-30 MHz band. The top-loaded monopole is shown to achieve 24 kHz bandwidth while maintaining a profile of less than 1 m which makes it ideal for vehicular applications. The practicality of a top-loaded monopole is considered and an umbrella is augmented to realize antenna and achieve desired functionality. A practical demonstration of umbrella performance on a real vehicle is also demonstrated to show this principle can also be exploited for all three modes of HF communications.