초록 ▼

A dual band antenna for mobile communications includes a rod-shaped radiating element having a first portion of a predetermined length connected to a coaxial feed line, and a second portion of a specified length integrally extended from the first portion. The coaxial feed line connects to a ground p

A dual band antenna for mobile communications includes a rod-shaped radiating element having a first portion of a predetermined length connected to a coaxial feed line, and a second portion of a specified length integrally extended from the first portion. The coaxial feed line connects to a ground plate, and a first capacitive load connects to the first portion of the radiating element. A choke surrounds the second portion of the radiating element, and has a shorting end connected to a distal end of the second portion and an open end at a proximal end of the second portion. A second capacitive load connects to the shorting end of the choke. In a higher operating band of the dual band, the input impedance of the choke is high, such that only the first (lower) portion of the radiating element radiates. At a lower operating band of the dual band, the choke's input impedance is lower to allow for radiation from the entire length of the antenna.

대표청구항 ▼

[ What is claimed is:] [1.] A dual band monopole antenna for mobile communications comprising:a rod-shaped radiating element having a first portion of a predetermined length connected to an inner conductor of a coaxial feed line, and a second portion of a specified length integrally extending from s

[ What is claimed is:] [1.] A dual band monopole antenna for mobile communications comprising:a rod-shaped radiating element having a first portion of a predetermined length connected to an inner conductor of a coaxial feed line, and a second portion of a specified length integrally extending from said first portion and having an outer surface;a ground plate connected to an outer conductor of said coaxial feed line; anda choke surrounding said outer surface of said second portion of said radiating element, said choke having a shorting end connected to a distal end of the second portion and an open end at a proximal end of the second portion to define an interior compartment longitudinally extending from said shorting end to said proximal end of the second portion.