Abstract: A printed 180 degree differential phase shifter includes a short nonuniform nonregular line and a uniform transmission line. The nonuniform nonregular line consists of two broadside coupled lines of both sides of a thin dielectric substrate. These highly magnetically coupled lines have short opposite connections (short circuits) connecting the coupled lines with a ground of the uniform line. An opposite input and output of the coupled lines are electrically interconnected with input and output transmission lines having equal impedances. The coupled lines are distant from the ground of the uniform line which can be any transmission line having an electrical length equal to the electrical length of the nonuniform nonregular line.

Abstract: A miniature directional coupler has short coupled lines, a series inductor and a parallel resistor connected to the second coupled line output. The coupled lines have a length considerably less than one quarter of a wavelength. Values of the series inductor and the parallel resistor are dependent on coupling, frequency, directivity, impedance and coupling flatness.

Abstract: A combined phase and frequency modulation device for modulating a data signal in order to generate a plurality of narrow band signals for a communication system is disclosed, characterized by a direct synthesis phase locked loop for generating an output data signal having a selected frequency, a signal divider and phase modulator circuit, and a frequency multiplier for multiplying a modulated signal to produce an output having a desired frequency. The signal divider and phase modulator circuit includes a frequency divider which produces two quadrature related signals from the output data signal. A modulator connected with the frequency divider generates a suppressed carrier double sideband signal from one of the quadrature related signals. A summing device connected with the frequency divider and with the modulator combines the carrier signal with the other quadrature related signal to produce the modulated output signal which is multiplied by the frequency multiplier.