A tunable-feedback ring-resonator oscillator using a voltage-controlled piezoelectric transducer (PET) is introduced. The new oscillator is constructed by a ring resonator with a pair of orthogonal feed lines as a feedback structure. The ring resonator with two orthogonal feed lines can suppress odd modes and operate at even modes. This operation shows a similar characteristic of high operating oscillation frequencies as that of the push-push oscillators. The high operating resonant frequency characteristic is predicted by a simple transmission-line model. The simulated and measured results agree well with each other. At a fixed frequency of 12.09 GHz, the oscillator has a high DC-to-RF efficiency of 48.7% with an output power of 5.33 dBm. A voltage-controlled PET is used to vary the resonant frequencies of the ring resonator, which, in turn, tunes the oscillator with a good tuning rage of 4.25% around 12 GHz. This tuned oscillator operating at high oscillation frequency can be used in many wireless and sensor systems.

High-efficiency piezoelectric-transducer-tuned feedback microstrip ring-resonator oscillators operating at high resonant frequencies

Push-push design has proven to be an efficient way to extend the usable frequency range of active devices for oscillator applications. In this paper, the basic principles of push-push oscillator design are explained and various possibilities to realize this concept are shown. Several examples of hybrid millimeter-wave push-push oscillators using SiGe HBTs as active devices are discussed. Details on large-signal modeling of the SiGe HBTs using both a vertical bipolar integrated-circuit model, as well as a customized large-signal model are given. Measured key performance data of microstrip resonator oscillators at 57 and 58 GHz are output power levels of +1 dBm and single-sideband phase-noise figures (1-MHz offset from carrier) of -106 and -108 dBm/Hz, respectively. For the dielectric-resonator oscillators, a maximum output power of -8 dBm and an optimum phase noise of -112 dBc/Hz (-14-dBm output power), as well as a mechanical tuning range of 500 MHz were measured.

Hybrid millimeter-wave push-push oscillators using silicon-germanium HBTs

There is a manufacturing limit on how small ceramic coaxial resonators can be produced, which leads to a limit on the frequency of resonance for these resonators. One technique to double the effective frequency of a ceramic coaxial resonator is to couple each end of a resonator to a Colpitts oscillator, the oscillators being balanced and out-of-phase by 180°. During operation, the resonator is effectively divided in half with a virtual ground forming in the center. This allows a single resonator to operate as two resonators of half the original size. Hence, the oscillation frequency for each of these balanced oscillators is doubled when compared to the frequency of similar oscillators that have separate ceramic coaxial resonators of similar size. This technique expands the range of use for a ceramic coaxial resonator so that, if implemented within a push-push architecture and if used along side a subharmonically pumped mixer that allows for doubling of the local oscillator frequency, the maximum oscillation frequency is increased to 40 GHz. This frequency range allows ceramic coaxial resonators to be used for high frequency applications such as LMDS.

Coaxial resonator and oscillation circuits featuring coaxial resonators

An oscillator with a balanced low noise amplifier has been designed and implemented through analysis of the Lesson's phase noise model. The Ku-band parallel feedback dielectric resonator oscillator is composed of a balanced low noise amplifier, a power divider in order to isolate the oscillator loop and output load, and a dielectric resonator bandpass filter for low phase noise.

Dielectric resonator oscillator with balanced low noise amplifier

The subject matter discloses a wireless communication system comprising: at least one active phased array antenna unit for transmission and reception of electronic radiation and a phased array circuit for driving and controlling said at least one phased array antenna unit, wherein said at least one phased array antenna unit comprises at least four one dimensional arrays of radiations. The subject matter also discloses a method for utilizing the described system.

Communication system and method using an active phased array antenna

A push-push injection-locked dielectric resonator oscillator has been designed for subharmonically injection-locked local oscillators in phased-array antennas at the K-band and above. This circuit topology has the following advantages: (i) a large subharmonic injection locking range using a dielectric resonator with a high quality factor: (ii) a larger frequency multiplication factor, while a microwave device, such as a MESFET, is operating at a low oscillation frequency and having an effective noise temperature (T/sub eff/) resulting in a reduction in frequency drift over the operating temperature and the intrinsic FM noise of the free-running oscillator: (iii) a higher yield rate in MMIC applications.

Joo-Yeol Lee

Papers

Push-push subharmonically injection-locked oscillator