Multimode antenna structure

A multimode antenna structure for transmitting and receiving electromagnetic signals in a communications device, the communications device comprising circuitry for processing signals communicated to and from the multimode antenna structure, the multimode antenna structure comprising:

• a plurality of antenna ports for coupling to the circuitry;
• a plurality of antenna elements, each operatively coupled to a different one of the antenna ports, the plurality of antenna elements arranged around a periphery of the multimode antenna structure;
• and
• a coupling element electrically coupling the plurality of antenna elements to a common point to form a single radiating structure, wherein electrical currents on one antenna element of the plurality of antenna elements flow to another antenna element of the plurality of antenna elements and substantially bypass an antenna port of the plurality of antenna ports coupled to the another antenna element such that an antenna mode excited by the antenna port of the plurality of antenna ports is substantially electrically isolated from a mode excited by another antenna port of the plurality of antenna ports at a given desired signal frequency range without coupling a decoupling network to the plurality of antenna ports, and the antenna structure generates diverse antenna patterns, wherein each antenna element of the plurality of antenna elements comprises two branches of different lengths to create resonance at two different frequencies.

An antenna structure for transmitting and receiving electromagnetic signals in a communications device, the communications device comprising circuitry for processing signals communicated to and from the antenna structure, the antenna structure comprising:

• a plurality of antenna ports for coupling to the circuitry;
• a plurality of antenna elements, each operatively coupled to a different one of the plurality of antenna ports, each antenna element of the plurality of antenna elements comprising upper and lower planar sections that are substantially parallel and spaced apart and a side section coupling the upper and lower sections;
• and
• one or more coupling elements, each electrically coupling to neighboring antenna elements of the plurality of antenna elements at one of the planar sections such that the plurality of antenna elements form a radiating structure, wherein electrical currents on one antenna element of the plurality of antenna elements flow to a neighboring antenna element of the plurality of antenna elements and substantially bypass one antenna port of the plurality of antenna ports coupled to the neighboring antenna element, wherein the electrical currents flowing through the one antenna element and the neighboring antenna element have a magnitude such that an antenna mode excited by the one antenna port is substantially electrically isolated from a mode excited by another antenna port of the plurality of antenna ports at a given desired signal frequency range without coupling a decoupling network to the plurality of antenna ports, and the antenna structure generates diverse antenna patterns, wherein each antenna element of the plurality of antenna elements comprises two branches of different lengths to create resonance at two different frequencies.