Showing papers on "Balun published in 1983"

Printed circuit balun with a dipole antenna

Abstract: A coplanar printed circuit balun for connecting an unbalanced feedline to a balanced dipole antenna.

R.F. Diplexing and multiplexing means

Abstract: Selection elements such as diodes or filters are provided for selectively grounding either one of the two unbalanced terminals of a balun. This allows either a signal, such as the R.F. signals from a VHF or a UHF antenna, applied to the other unbalanced terminal of the balun to be selectively coupled to the balanced terminals of the balun in a diplexer arrangement. In a tuner, the balun may be used as part of a doubly balanced mixer. In another embodiment, the balanced terminals are used as inputs and the unbalanced terminals are used as outputs with the selection elements coupled to the outputs to form an R.F. multiplexer.

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.

Waveguide/microstrip mode transducer

Abstract: A waveguide/microstrip mode transducer operable over a broad frequency range comprises a dielectric substrate (3) extending along an E-plane of a waveguide and having a conductive layer on each major surface, the two layers having three successive pairs of portions. A first pair (10, 11) form a microstrip line, a second pair (12, 13) form a balanced transmission line, and a third pair (14, 15) couple the portions (14, 15) of the balanced line to opposite walls (6, 7) of the waveguide. The microstrip line is coupled to the balanced line in a manner which is independent of frequency over the operating frequency range, rather than by a resonant balun; the strip conductor portion (10) and the ground plane conductor portion (11) of the microstrip line respectively are the same width as, and taper smoothly to the width of, the conductor portions (12, 13) of the balanced line connected thereto, and there are two regions (22, 23) respectively on opposite sides of the balanced line in which there is no conductor on both surfaces of the substrate (3 ) and which exhibit no resonance in the operating frequency range. In order to provide phase velocity matching between the waveguide and the transmission lines on the substrate (3), particularly when the substrate (3) has a high dielectric constant, the substrate (3) has a recess (24) of progressively increasing width along the waveguide.

Signal distributing apparatus

Abstract: A signal distribution apparatus for selectively coupling each of a plurality of inputs to one or both of two outputs substantially without interference between the inputs or the outputs. The signal distributing apparatus comprises a plurality of input terminals and balanced couplers, such as balun coils, for providing a balanced line from each input terminal. A switching network is coupled intermediate the balanced couplers and the two outputs for selectively and individually coupling each balanced line to one or both of the outputs.

Balance Quality Measurements on Baluns

Abstract: Two different methods of measuring the balance quality of baluns are described. Section I describes the balance comparator, a mechanical test device requiring only a signal source, and receiver to perform the measurements on the test balun. Section II describes the use of a network analyzer, computer controlled to plot out all the graphical data on the balun measurements. Measurements on a balun having known balance characteristics show both methods obtain satisfactory balance data.

UHF/VHF Splitter-balun assembly

Abstract: A signal splitter-balun assembly for coupling a UHF antenna and a VHF antenna to a single input terminal of a television receiver is disclosed. RF isolation is provided by means of appropriate filtering, 60 Hz isolation is provided by means by a pair of capristors, and the required impedance transformation is provided by means of a conventional balun transformer in a low cost unit utilizing a minimum number of components.

Broadband loop antenna with low wind resistance

Abstract: An antenna for CP signals uses a reflector, such as a truncated pyramid. Feed tubes, which act as a balun extend from the pyramid. Four truncated square loops are coupled to the feed means. The truncation results in a smaller radome being used and hence smaller wind resistance. A feed strap has a capacitance hat for a better match.

Double balanced mixer device

Abstract: PURPOSE:To attain low current consumption by connecting a constant current circuit to a source side without giving any effect on a high frequency signal to suppress the increase in an AC operating current attended with the increase in a local oscillating signal voltage. CONSTITUTION:In the figure, (k) is the constant current circuit, a control voltage is applied to a gate of an FET12 via a resistor 13 from a terminal (l), and a drain current of the FET12 is made constant so as to make the sum of source currents of a double balanced mixer (d) constant via a balun (c). Thus, a local oscillating signal enters the balun (a) from a local oscillating signal input terminal (e), supplied to a gate of FETs 1d, 2d, 3d and 4d and when the power is increased to >=10dBm, the current flowing to the circuit, i.e., the sum of source currents of the double balanced mixer (d) remains a slight increase within several mA to the current set by the constant current circuit (k). A high frequency signal enters the double balanced mixer (d) via the balun (c). Since the connecting point between the constant current circuit (k) and the balun (c) is grounded in terms of high frequency by a capacitor 10, the effect of the constant current circuit is avoided.

Die pole antenna

Abstract: PURPOSE:To obtain an easily manufactured die pole antenna with high precision by printing two die poles, feeders, a multiplexer, and a balun on one dielectric substrate. CONSTITUTION:The die poles 9a and 9b, and 10a and 10b are printed on the top and reverse surfaces of the dielectric substrate 8 and fed through printed parallel two-wire lines 11a and 11b, and 12a and 12b. The die poles each have a center point of feeding and cross to each other at right angles. The length of the parallel two-wire line from a branch point A to each die pole through a coaxial plug 14 and the tapered balun 13 is so determined that a 90 deg. phase difference is obtained. Therefore, the die pole antenna in a figure radiates a circular polarized wave.

Balun for microwave

Abstract: PURPOSE:To obtain a broad band balun by converting the microstrip line propagating mode into the slot line propagation mode and obtaining signals of in- phase and opposite phase in converting again the converted mode into the microstrip line propagation mode. CONSTITUTION:A signal propagated to an input microstrip line 7 in the form of a downward electromagnetic field is propagated through a slot line 4 after the electromagnetic field is converted into a rightward electromagnetic field. The field is converted again into the downward electromagnetic field at an output microstrip line (MSL) 8 because the line is short-circuited to a conductor 6 with a through-hole 11, and an in-phase output signal S0 to the input signal is obtained from an end part of a conductor 8A. The downward electromagnetic field is converted into an upward electromagnetic field because other output microstrip line 9 is short-circuited with a conductor 5 on the other side of the conductor by which the input line 7 is short-circuited, and an output signal with opposite phase to that of the input signal is obtained from the end part. Each electric path length from the input to each output is set identical.

Double balanced type broad band multiplier

Abstract: PURPOSE:To eliminate the limit of the maximum frequency and to use the titled multipliers at a region >=3GHz, by connecting unbalanced terminals of band conductors to external conductor lines and using the unbalanced terminals of band conductors placed at the center as an input terminal and an output terminal CONSTITUTION:In Figure, a microwave signal applied to the input terminal 10 is applied to multiplying diodes 6-9 via 1st three-conductor coplaner type lambda/4 microwave balun 12 Harmonics generated at the diodes 6-9 appear at the output terminal 11 via the 2nd three-conductor coplaner type lambda/4 microwave balun 13 The diodes 6-9 are bridge-connected so as to obtain even-order harmonics Thus, the input signal having an angular frequency omega1 applied to the input terminal 10 appears at the output terminal 11 as the output signal having 2nomega1 of angular frequencies To obtain odd-order harmonics, the connection is to be changed

A Double Balanced Finline Mixer with Broad if Bandwidth Capability

Abstract: A novel double balanced mixer (DBM) design is reported, which is suitable to cover very broad IF-bandwidths, and overcomes the problem of IF-bandwidth restriction, co. mon to many other DBft's. The mixer utilizes bilateral finline at the RF-input and a tapered balun at the IF-output. The circuit can be produced up to the mm-wave range using low-cost planar transmission line techniques. Features of the nev design are demonstrated at the example of a mixer, that dovnconverts the entire K-band (18-26.5 GHz) to intermediate frequencies anywhere between 2-16.5 GHz or serves as an upconverter, thus extending the bandwidth of a network analyzer.