W-band MMIC direct detection receiver for passive imaging system

Abstract

We have demonstrated for the first time W-band MMIC direct detection receivers for passive millimeter-wave imaging applications. These receivers were developed using InGaAs HEMT based W-band LNA and preamplified detector MMICs. The first receiver uses a 50 dB gain, 6 dB noise figure amplifier and a Schottky barrier diode waveguide detector. The amplifier uses four W-band MMIC LNAs. The second receiver consists of two 3-stage MMIC LNAs and a MMIC preamplified /detector chip. Individual receiver was integrated with a millimeter-wave camera system. Field imaging acquisition runs were performed using the camera in stepping pushbroom image acquisition mode with excellent results.

Millimeter-Wave and Sub-THz Phased-Array Imaging Systems Based on Electro-Optic Up-Conversion and Optical Beamforming

“…which may be split into the following two terms: The first term in ( 6) is identified as the intensity produced by the carrier wavelength of the modulated signal (no spectral filtering was applied in the calculations). It contains no information about the scene except for the total power that is shifted from the carrier frequency to the sidebands, 1 The two terms in (7) can be identified as two images reconstructed from the two sidebands of the modulated optical beam. They differ in the sign between the phases on the antenna side km and on the optical side nm.…”

“…In the 1970s and 1980s their development evolved into linear and conical scanning systems [3]- [5]. The 1990s saw significant developments in microwave monolithic integrated circuits (MMICs) [6], [7], which led to lens-based [8], [9] mmW focal-plane-array (FPA) imaging systems [10]- [15]. In the late 1990s and early 2000s novel scanning and phased-array implementations were introduced [16]- [18] and in the 2010s, systems based on diode Manuscript received 2 February 2023.…”

Optical Performance Analysis Using a Point Spread Function and Modulation Transfer Function for W-Band PMMW Imaging System Based on Quasi Optics Focused Array of Dielectric Rod Waveguide Antenna

“…This imaging is typically performed using a single or a linear array of the focused detector † to raster scan the scene [4,5]. The PMMW camera was also developed using the same configuration similar to what is commonly used in visible and IR camera [6,7], i.e., the 2D array of the focused detector [6][7][8][9][10][11][12].…”

“…In order to get a high resolution millimeter wave image, various types of detectors have been tried for the feed element in the focal plane array (FPA) based quasi optical imaging systems at W-band [8][9][10][11][12][13][14]. The spatial resolution of a focal plane array system very much depends on the spacing of its feed elements in the detector array.…”

“…Antennas fabricated on planar substrates have been tried by many researchers [8][9][10][11][12]. Despite the compact size of a planar antenna array on substrate, one important limitation of this type of antenna array is the loss caused by surface waves propagating along the substrate.…”