Design and Implementation of DC–20-GHz Lumped Resistor Matched Loads for Planar Microwave Circuits

Abstract

In this paper, a design technique to match lumped resistors in the dc to 20-GHz band is presented. This technique makes it possible to implement very wideband matched loads with a return loss that is better than 20 dB. The proposed implementation is simple, low cost, and gives superior performance than previously reported alternatives. The technique was developed to match surface-mount resistors soldered on plastic substrates, and was then successfully applied to match trimmed printed resistors on low-temperature co-fired ceramic substrates.Index Terms-Low-temperature co-fired ceramic (LTCC) circuit, matched load, planar microwave circuit, printed resistors, wideband.

Matched loads using substrate integrated waveguide and shaped absorbing material for KA‐/Q‐band applications

“…The MIMO (multiple input multiple output) technology has played an important role in the 4G/5G communication system in terms of the data rate improvement and the wireless channel capacity expansion in the rich scattering environment [1]. They primarily depend on the antenna diversity, including the spatial, radiation pattern, frequency [2], and polarization diversity. The remarkable feature of the MIMO system is that the multiple antennas are applied both in the transmitting and receiving terminals.…”

“…Hence, it follows (2) strictly, only associating with its normal direction incidence and reflection, and inner transmission loss. According to (2), two elements are significant to the matched load. One is good impedance match at each boundary of two adjacent mediums, which can contribute to a low Pr.…”

“…In literatures, some matched loads have been implemented in various approaches. The planar lumped resister matched load developed in [2] performs quite well from dc to 20 GHz; but it is difficult to operate at higher frequency owing to the increased parasitic effects of the lumped resistor. Moreover, the resistive thin film (RTF) and carbon nanotubes have been utilized to enhance bandwidth of matched loads [3,4].…”

Microwave power thin film resistors for high frequency and high power load applications

“…[1][2][3][4][5] It is typically used as dummy load or power-absorbent at the normally isolated ports of, such as, circulators as well as couplers to absorb the extra power caused by mismatches, imperfect directivity, or imbalances somewhere in these systems. By this way, the rear-end components or systems can be avoided from being burned or destroyed.…”

“…The area of each TaN thin film was 9 mm. 2 The dc resistance of each resistive film was 50 ⍀, so the dc resistance of the overall MPTFR is 25 ⍀. Silver was used as the electrode materials.…”