Patent
Voltage controlled oscillator with correction of tuning curve non-linearities
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TLDR
In this paper, a stable combline oscillator is used to generate known frequency signals which are frequency converted to an intermediate frequency (IF) using the local oscillator and frequency converter(mixer).Abstract:
A scanning-superhetrodyne ESM receiver having a VCO for a local oscillator which is linearized and temperature compensated. A stable combline oscillator is used to generate known frequency signals which are frequency converted to an intermediate frequency (IF) using the local oscillator and frequency converter(mixer). The frequency of each combline signal is measured and a table of known voltage/frequency points is generated. The table is input to a Cubic Spline program which computes the coefficients for the best-fit third order polynomial for each pair of data points. When a particular local oscillator frequency is desired, the corresponding tune voltage is computed by solving the polynomial equation for the given frequency range. By repeating the calibration on a periodic, or an "as needed" basis, temperature compensation is achieved.read more
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Patent
Adaptive radio transceiver with a local oscillator
TL;DR: In this paper, an oscillator circuit consisting of a first signal having a first frequency, a second oscillation source having a second frequency, the second oscillator comprising a frequency divider coupled to the oscillator, and a mixer to mix to the first and second signals is described.
Patent
Adaptive radio transceiver
Ahmadreza Rofougaran,Maryam Rofougaran,Meng-An Pan,Hung-Ming Chien,Shahla Khorram,William T. Colleran,Jacob Rael,Masood Syed,Brima Ibrahim,Stephen Wu,Shervin Moloudi +10 more
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Patent
PLL Fast frequency synthesizer with memories for coarse tuning and loop gain correction
TL;DR: In this article, a phase-locked loop frequency synthesizer is used for providing an output signal whose frequency jumps from one value to another, at regular intervals of time, at each time a new frequency is selected.
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Automatic calibration device for direct spectrum spread receiver
TL;DR: In this article, a simulated reception signal is produced by modulating an AC signal having the same frequency as the reception frequency with a modulating signal produced using two pseudo noise codes delayed by 1/2 or 3 chips.
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Local oscillators for radio receivers
TL;DR: In this article, an error detector is used to detect an error in the frequency of the VCO on the basis of a received signal processed with the oscillating signal from the VOC, a temperature probe and a memory.
Patent
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Patent
Heterodyne phase lock system
TL;DR: In this paper, a heterodyne phase lock system is disclosed having a plurality of oscillator circuits, at least one of the oscillator circuit being a voltage controlled oscillator (VCO) circuit, and the control circuit includes a phase lock circuit, which is responsive to an applied reference signal for adjusting the output of the VCO.