A precision vector network analyzer which is suitable for a wide range of applications including both laboratory and automated production measurements and testing is disclosed. New measurement capabilities, greater ease of use, and nearly complete automation are provided. Contributions include fully coordinated communications between subsystem modules; real time, two channel, precision vector measurements with complete, internal error correction; wide frequency capability from RF to millimeter bands; combined time and frequency domain analysis and display; measurements either in the swept or step frequency modes; and user definable test functions and calibration device sets.

Vector network analyzer with integral processor

An integrated low-IF (low intermediate frequency) terrestrial broadcast receiver and associated method are disclosed that provide an advantageous and cost-efficient solution. The integrated receiver includes a mixer, local oscillator generation circuitry, low-IF conversion circuitry, and DSP circuitry. And the integrated receiver is particularly suited for small, portable devices and the reception of terrestrial audio broadcasts, such as FM and AM terrestrial audio broadcast, in such portable devices.

Integrated low-if terrestrial audio broadcast receiver and associated method

A measurement unit U100 measures an input signal to be measured by sweeping frequencies in a measurement range having a predetermined frequency band so as to obtain waveform data to be developed on the frequency axis such as spectrum data in, e.g., a spectrum analyzer. The waveform data obtained by the measurement of the measurement unit U100 is displayed by a display device 500 via a display data processor U20 included in a control unit U200 to be described later to be developed on the frequency axis of the display device, i.e., in correspondence with the measurement frequencies. The control unit U200 includes a measurement controller U30 for controlling the measurement unit U100 so as to display waveform data obtained by enlarging or reducing waveform data, before a measurement frequency condition is changed, at a predetermined magnification to have a predetermined point on the frequency axis as the center on the basis of a change in measurement frequency condition set by a condition setting unit U900, and an enlargement display/stable display processor U40 for controlling the display data processor U20. The enlargement display/stable display processor U40 realizes high-definition waveform observation as the gist of this invention, and substantially has a function of controlling the display device U500 as the control unit U200.

Waveform display apparatus for easily realizing high-definition waveform observation

An inexpensive portable RF (radio frequency) microcontroller-based (76) digital spectrum analyzer (50) is automatically calibrated for passband amplitude tilt/variations. Resulting software-obtained (78) calibration parameters are used during operation to reduce or eliminate passband amplitude errors. The spectrum analyzer (52) also includes a PLL frequency synthesizer (100) arrangement, but the PLL (100) controls a VCO only during calibration to derive calibration values for controlling a digital-to-analog converter (92). During normal operation, the VCO is driven in an open loop configuration under software control using such calibration values -- achieving nearly the accuracy of closed loop operation while avoiding the penalty of long PLL lock time. These amplitude and frequency calibration techniques and arrangements permit the spectrum analyzer to have relatively inexpensive components and circuit arrangements and nevertheless achieve high accuracy over a wide band.

Inexpensive portable rf spectrum analyzer with calibration features

Disclosed are systems and methods for transmitting obtained vehicle diagnostic data to a separate display device. The method includes a first vehicle diagnostic device obtaining vehicle diagnostic data via a vehicle interface to a diagnostic port of a vehicle, determining whether a direct wireless connection with one or more display devices is available, and determining whether an indirect wireless connection with the one or more display devices is available via a second separate vehicle diagnostic device. Responsive to a further determination, the vehicle diagnostic device may transmit the obtained diagnostic data to the one or more display devices via the second separate vehicle diagnostic device. The further determination may be based on one or more of wireless connectivity status, power level status, transmission power requirements, or other facts or determinations.

System and method for extending communication range and reducing power consumption of vehicle diagnostic equipment

An input signal is mixed with sampling signals from oscillators which vary the frequency of the sampling signal from a first frequency to a second frequency. The resulting Intermediate Frequency (IF) signal is processed and digital values are stored in a memory in response thereto. Waveforms are then displayed which correspond to these frequency and amplitude values. Various input and display circuits facilitate the display and interpretation of these waveforms.

Larry R. Martin

Papers

Apparatus for spectrum analysis of an electrical signal