Balun

About: Balun is a research topic. Over the lifetime, 5375 publications have been published within this topic receiving 52256 citations. The topic is also known as: Telephone balance unit.

A Compact Planar Quasi-Yagi Antenna With Bandpass Filtering Response

Abstract: A planar quasi-Yagi antenna with bandpass filtering response is presented. The quasi-Yagi antenna consists of a double-sided printed driven dipole, an offset double-sided parallel-strip line (DSPSL) director, a DSPSL reflector, and an offset DSPSL parasitic element. Both the reflector and the parasitic element can produce an extra radiation null at the band-edges of the passband, and the parasitic element can also generate an additional resonance within the passband. As a result, a compact wideband quasiYagi antenna with quasi-elliptic bandpass filtering response is obtained, without requiring any extra filtering circuit. In addition, the antenna is fed by a balanced DSPSL, and therefore, no balun is needed, leading to a very simple feeding structure. For demonstration, a prototype operating at 2.4 GHz was designed and measured. The prototype has a low profile of 0.006λ0, a -10-dB impedance bandwidth of 30.4%, an average gain of 5.7 dBi over the passband, and an out-of-band suppression level of about 20 dB in the near stopbands.

Integrated quadrature splitter-combiner and balun

Abstract: An integrated quadrature splitter-combiner and balun comprising: a transmission line balun operably connected to a first port and a second port; a first capacitor operably connected across the transmission line balun; a second capacitor operably connected to the first port and said balun; and a third capacitor operably connected to the second port and the balun. The second capacitor, the third capacitor, and the transmission line balun combine to form an RF splitter-combiner to split a balanced RF signal received at the first port into a first and second unbalanced quadrature RF signal transmitted at the second port and combines the first and second unbalanced quadrature RF signals received at the second port into the balanced RF signal transmitted at the first port.

Balancing and unbalancing converter

Abstract: PURPOSE:To reduce stray coupling of a coupler and to attain a balun with broad band by using two 1/4 wavelength parallel line couplers of open end and short-circuit end. CONSTITUTION:A signal impressed to an unbalanced input terminal 309 is transmitted to terminals 303 and 307 at the same level and phase and appears at terminals 304, 308 with the same level. Since the phase is led by 90 deg. at the terminal 304 in comparison with that of the input signal and delayed by 90 deg. at the terminal 308, the phase difference between the terminals 304 and 308 is 180 deg. and the signal is utilized as a balanced output. Thus, since the balanced output terminal is taken from the same direction by the constitution above, the wiring of lines is minimized, the phase characteristic is improved and then the coupler is constituted by two independent coupling sections, allowing to reduce the stray coupling of the coupler and the balun with broad band is attained by using the coupler having a strong coupling degree.

Electronically adjustable balanced-to-unbalanced converters (balun)

Abstract: Electronically adjustable baluns and electronically adjustable balanced-to-unbalanced converting methods are provided. The electronically adjustable baluns are responsive to an electronic tuning signal to electronically vary the frequency range thereof. The baluns may include an electronically variable transformer, capacitor or inductor or switched transformers, inductors or capacitors, or combinations of these elements.

Inline coaxial balun-fed ultrawideband cornu flared horn antenna

Abstract: The inline coaxial balun fed cornu flared horn antenna is formed by transitioning a coaxial transmission line to a parallel-plate transmission line with a Klopfenstein impedance profile and terminating with a flared horn antenna based on a scaled cornu spiral. The cornu spiral is a mathematical plane curve formed by parametrically plotting the scaled cosine Fresnel integral versus the scaled sine Fresnel integral. The antenna has the property that the curvature of the flare increases linearly in proportion to the arc length of the flare. The Klopfenstein impedance profile of the inline balun ensures a low voltage reflection across a wide bandwidth with a minimum transition length and together with the cornu flare satisfies the requirements for a wideband design. The design efficiently radiates and receives a high power pulse of ultrawideband electromagnetic waves over a preferred range of angles in space and transmits a field that is nearly the scaled temporal derivative of the input voltage signal and receives a voltage that is nearly the scaled replica of the incident field.