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This article provides an overview of the use of millimeter-wave (mmWave) imaging in security scanning systems. MmWave scanners are capable of detecting both metallic and nonmetallic threats, making them more effective than traditional metal detectors. The article explains the functioning of mmWave imaging, including the role of transmitters, receivers, and antennas. It introduces a chipset developed by Analog Devices that utilizes edge processing to handle the large amount of data generated by mmWave scanners. The chipset includes a transmitter (ADAR2001) and a receiver (ADAR2004) that work together to create a complete mmWave scanner. The article highlights the importance of fast switching times and the ability to differentiate between different objects in security scanning scenarios. It also discusses the various components of the chipset, such as the ADAR2001 quad transmitter, ADAR2004 quad receiver, AD9083 16-channel ADC, and ADF4368 PLL/VCO chipset, which can be used to develop advanced mmWave security scanners. The chipset offers integrated state machines and on-chip digital downconversion, which enhance processing efficiency. The article further explains the sequencing and operation of these devices, as well as the advantages of utilizing multiple transmit frequencies. Additionally, the wide frequency range and high channel density of the chipset suggest potential applications beyond security imaging. [Extracted from the article]

CAPACITY AND BANDWIDTH EFFICIENCY IN CURRENT AND EMERGING wireless communications formats such as Long Term Evolution (LTE) systems are driving the design of smaller base stations with multiple-carrier capabilities. The [...]

Wireless transmitters can benefit from measurement and control of RF power. Because of such factors as regulatory requirements and the need to co-exist with other wireless networks, the RF power [...]

Following Is A Practical Guide To Designing Low-Power, Low-Distortion Circuits For XDSL And Cable Modem Systems. Even though highly integrated chip sets for wired communications standards such as High Bit-rate […]

The Current Breed Of High-Speed Op Amps And Applications Are Making Manufacturers Rethink The Way They Specify These Devices. The semiconductor industry has basically been using the same specifications to […]

Rail-to-Rail Op Amps Can Save Power And Lower Distortion If Careful Attention To Detail Is Paid. Line driving is a critical function in all wired digital communications applications. In general, […]

Analog Devices Inc. of Wilmington, MA, introduces the new high-frequency, multi-stage AD8313 logarithmic amplifier, which is capable of assisting over a wide dynamic range direct RF-signal-strength measurement. The new AD8313 logarithmic amplifier, which is appropriate for power-control and RF-measurement functions at frequency levels of up to 2.5 GHz, assists users by facilitating the determination of receivers and transmitters' transmitted signals over a wide dynamic range. Analog Devices equips its new logarithmic amplifier technology with its standard approach for successive detection.

Victor Chang and Eamon Nash, Analog Devices, Wilmington, MA MODERN HIGH-PERFORMANCE transmitters require accurate monitoring of RF power, because most cellular standards depend on strict power-transmission levels to maintain an [...]

By looking at how a serial inter face works, we will dispel some myths about serial data converters. The key difference between serial and parallel data converters obviously lies in [...]

The article presents guidelines on how system engineers can understand the contribution of individual components to the overall performance of a device. For a three-stage signal chain, system engineers can use cascaded noise factor, gain, composite third-order intercept (IP3) and 1 dB Compression (P1dB) equations. System engineers can use the ADIsimRF radio frequency (RF) signal chain calculator from Analog Devices.

Because of their fundamental rectifying characteristic, diodes have been used to generate DC voltages that are proportional to AC and RF signal levels for as long as there have been diodes. This article compares the performance of diodebased RF/microwave detectors with integrated circuit alternatives. Topics include transfer function linearity, temperature stability and interfacing with analog-to-digital converters. [ABSTRACT FROM AUTHOR]

Explains the uses of logarithmic amplifier (logamp) technology in detecting catastrophic events such as the sudden increase in voltage standing-wave ratio that might occur when an antenna breaks. Application of logamp in the global system for mobile communication transmitter; Use of a closed-loop architecture; Illustration of a wireless transmitter with an auxiliary receiver in which the signal being transmitted is sampled and mixed back down to baseband; Means by which calibration is performed.

Examines the direct-conversion approach for multicarrier WCDMA and CDMA2000. Comparison of single-carrier and multiple-carrier transmitter spectra; Key advantage of the super heterodyne architecture over a direct-conversion approach; Goal of the transmitter signal-chain designer.

Focuses on taking advantages of fast rail-to-rail op amplifiers in low-voltage systems. Protection of analog inputs; Gains and adjustments; Signal distortion; Design examples; Video line drivers; Loading conditions. INSET: Making the swing..

Focuses on the implementation of an automatic gain control (AGC) amplifier using a voltage-controlled amplifier (VCA) and a single supply voltage-feedback amplifier configured as an integrator. Direct current representation of the VCA output signal; Lower trace illustration of the voltage at the AGC amplifier's output.