Abstract: A nonlinear transmission-line waveform generator for generating a comb of frequencies and relatively short duration pulses, for example, in the range of picoseconds and tens of picoseconds, that are adapted to being utilized with ultra wideband radios in order to improve the bandwidth of such radios by an order of magnitude, for example, up to tens and even hundreds of GHz. In particular, the nonlinear transmission line waveform generator in accordance with the present invention consists of a microstrip or coplanar waveguide line. In accordance with an important aspect of the invention, the &Dgr;C/&Dgr;V characteristic of the nonlinear transmission line is matched to the frequency and amplitude of the input sinusoidal waveform.

Abstract: An acoustic charge transport device is formed by a process which introduces a process dependent variation in charge carrier density within the device. The acoustic charge transport device includes a transport channel operable to carry charge carriers in response to a surface acoustic wave. In addition, the acoustic charge transport device further includes a backgate for controlling the charge carrier density within the transport channel.

Abstract: A programmable phase shifter (20, 40, 54, 60, 62) includes a variable delay line formed from a nonlinear transmission line (NLTL) (26, 28, 46, 28), which enables the device to be used in applications where the frequency of the input signal varies. A variable DC bias applied to the NLTL (26, 28, 46, 48) varies the NLTL's phase velocity and delay. Since the characteristic impedance of a transmission line changes as a function of the DC bias, the input voltage standing wave ratio (VSWR) also changes. In order to compensate for the change in the input VSWR, a pair of NLTLs (26, 28, 46, 48) are coupled at the input and output to a pair of hybrid couplers (22, 42). In an alternate embodiment of the invention, the hybrid couplers (22, 24) are replaced with 180° power splitters (42, 44) in order to reduce distortion of the device. In other embodiments of the invention (40, 54), a nonlinear transmission lines are used to form both discretely variable and continuously variable digital phase shifters (60, 62).

Abstract: A nonlinear transmission-line waveform generator for generating a comb of frequencies and relatively short duration pulses, for example, in the range of picoseconds and tens of picoseconds, that are adapted to being utilized with ultra wideband radios in order to improve the bandwidth of such radios by an order of magnitude, for example, up to tens and even hundreds of GHz. In particular, the nonlinear transmission line waveform generator in accordance with the present invention consists of a microstrip or coplanar waveguide line. In accordance with an important aspect of the invention, the &Dgr;C/&Dgr;V characteristic of the nonlinear transmission line is matched to the frequency and amplitude of the input sinusoid. By matching the &Dgr;C/&Dgr;V characteristics of the nonlinear transmission line to the input sinusoid, the output of the nonlinear transmission line produces a comb of frequencies that are multiples of the input sinusoid frequency, making it suitable as a harmonic generator.

Abstract: A relatively narrow fractional bandwidth saw filter formed on a standard ST cut of quartz. The electrode pattern is modified in order to eliminate distortion. In particular, the overlap pattern is formed with one or less active overlaps per wavelength in those regions of the SAW filter where the weighing function is maximum. A plurality of six finger/.lambda. electrode patterns with two active overlaps per wavelength is also provided.

Abstract: A relatively narrow fractional bandwidth saw filter formed on a standard ST cut of quartz. The electrode pattern is modified in order to eliminate distortion. In particular, the overlap pattern is formed with one or less active overlaps per wavelength in those regions of the SAW filter where the weighing function is maximum. A plurality of six finger/.lambda. electrode patterns with two active overlaps per wavelength is also provided.