Passive Power Combiner Research Articles

Investigation of compact broadband quasi-planar rectangular ring cavity power-combining amplifier

ABSTRACTA compact broadband quasi-planar rectangular ring cavity (RRC) power-combining amplifier is presented. To realize the broadband impedance matching, high assembly precision, and the strong coupling between the RRC and the output ports, the novel inserted ground waveguide probe structure was proposed. The measured insertion loss of the passive power combiner is increased from 0.6 to 1.7 dB at the bandwidth 6.5–14.2 GHz. The measured small-signal gain of the four-device power-combining amplifier is 22.2–26.7 dB over a broadband from 8 to 14 GHz. The measured maximum output power at 1-dB compression is 37.7 dBm at 11.4 GHz, with a power-combining efficiency of about 89%. The measured results of the passive power combiner agree with the simulated ones closely.

Power Combiner for High Power Cerenkov Devices

Two Cherenkov devices are effectively combined using a circular waveguide T-junction in a simulation study. The microwave sources are driven by the same high voltage pulser to prevent phase difference at the output of the power combiner. This passive power combiner not only combines the microwave power, but also outputs a Gaussian beam when a TM01 mode is used as the input. An efficient serpentine mode converter has been used as the basis of the power combiner design where the fields sum up at the common section of the two mode converters. A combined summation/conversion efficiency was $\sim 90$ % when the output power was more than 1.8 times the input power with a Gaussian output pattern. The combined microwave power was more than 600 MW at 10.2 GHz.

Innovative Theory on Multiband NGD Topology Based on Feedback-Loop Power Combiner

The signal delay is one of the main issues encountered during the design and fabrication of the RF/microwave electronic circuits and systems. Therefore, the correction process is constantly needed for the signal delay cancelation. This brief introduces an innovative theory of a microwave circuit topology delay suppressor. The original circuit was originally built with a passive power combiner (PWC) in feedback with an interconnect transmission line (TL) without the use of lossy lumped elements. The theoretical formulation proves that the distributed passive circuit is capable of generating the negative group delay (NGD) phenomenon. The synthesis relations enabling us to determine the circuit parameters in function of the desired NGD value are established. The innovative NGD circuit properties are elaborated. The NGD concept validation was verified with the design of fully distributed passive NGD cell built with a Wilkinson PWC in feedback with a lossy transmission line. The influence of the feedback line attenuation on the NGD function and S-parameters is discussed. A multiband NGD of about -0.7 ns was exhibited over the frequency band of about 0.12 GHz. This distributed NGD topology can be integrated and is useful for the microwave signal delay improvements.

Broadband Millimeter-Wave Power Combiner Using Compact SIW to Waveguide Transition

A novel broadband millimeter-wave passive power combiner based on substrate integrated waveguide (SIW) to waveguide transition is presented in this letter. Two transition circuits are symmetrically inserted into the E-plane of the rectangular waveguide and function as power-combining network. To satisfy the wideband request of the power combiner, a broadband and compact SIW-to-waveguide transition circuit has been developed using antisymmetric tapered probe. A Ka-band four-way power combiner was fabricated and the measured results agree well with the simulated ones. The measured results show that the proposed combiner achieved a bandwidth of 52% from 23.5 to 40 GHz with better than 15 dB return loss and an insertion loss of 0.75 to 1.4 dB. This millimeter-wave power combiner can be employed in high power-combining system for its simple structure and broadband performance.

Millimeter-wave waveguide-based out-of-phase power divider/combiner using microstrip antenna

A millimeter-wave waveguide-based out-of-phase power divider/combiner using microstrip patch antenna has been proposed in this paper. The stepped rectangular waveguide provides smooth impedance matching from standard rectangular waveguide to oversized rectangular waveguide. In order to obtain good amplitude balance, four symmetrical microstrip patch antennas are utilized. A Ka-band four-way passive power combiner is designed and measured. The measured results show a reasonable agreement with the simulated ones.

Optimal Matched Rectifying Surface for Space Solar Power Satellite Applications

In this paper, we propose a microwave energy reception approach for space solar power satellite applications based on the concept of artificial perfectly matched layer. By embedding rectifying diodes into well-designed metamaterial cells, the obtained rectifying surface simultaneously exhibits a nearly perfect impedance matching to the air and the rectifying circuits, and a strong impedance mismatching to the air at harmonic frequencies, leading to a simple structure that can be implemented using commercial multi-layer printed circuit board technology. The fabricated sample shows that, with a thickness of nearly 1/40 of the free-space wavelength, this rectifying surface has an experimental power absorption rate of 99.92% under normal incident power density of 0.1 mW/cm2, and a 56.16-dB suppression to the second-order harmonic. The measured rectifying efficiency complies well with the theoretical expectation. By introducing an additional layer of passive power combiner network, the proposed approach can also be used in applications of harvesting weak ambient RF and microwave energy. We expect a wide range of applications to emerge from this novel concept in the future.

Sub-THz Four-Way Waveguide Power Combiner With Low Insertion Loss

A four-way waveguide power divider has been developed in sub-THz band. The waveguide power divider was achieved with the improved H-plane T-junction structure. By tuning the depth and width at the junction of the waveguide, the input impendence was matched and the two-way output power amplitude and phase were at the same level. The four-way power divider was realized by the concatenation of two same T-junction at the two output ports. A sub-THz four-way passive power combiner is designed, fabricated and measured. The measure results show that the measured insertion loss of the fabricated four-way passive power combiner is less than 1.2 dB whereas the input return loss is greater than 14.8 dB from 97.5 to 101.7 GHz. Experiments on the sub-THz four-way passive power combiner show that a minimum insertion loss of 1 dB has been achieved at about 99.5 GHz. The measured minimum insertion loss of the waveguide power divider is half of the insertion loss for the entire passive power combiner (0.5 dB), which corresponds to a power-combining efficiency of 89 %. The measured results agree with the simulated ones closely.

Millimetre‐wave quasi‐optical low‐loss power combiner based on dipole antenna

A novel millimetre-wave quasi-optical low-loss power divider based on the dipole antenna is presented. This dipole antenna array is inserted in the E-plane of the rectangular waveguide to implement the power-dividing function. A Ka-band four-way passive power combiner is designed, fabricated and measured. The measured results show that the minimum insertion loss is about 0.4 dB from 32.1 to 34 GHz, whereas the return loss is less than 10 dB from 31.5 to 35.9 GHz. The measured results agree with the simulated ones closely.

Compact U-band 32-way ring-cavity spatial power combiner with low insertion loss

A novel compact millimetre-wave 32-way ring-cavity power dividing/combining circuit is presented. The ring-cavity power dividing function and the symmetric electromagnetic-field excitation is investigated. A U-band 32-way ring-cavity passive power combiner is developed with reasonable agreement between the simulated and measured results.

A Novel Compact UWB Power Divider for Spatial Power Combining

A novel ultra wideband (UWB) power divider applied in spatial power combining is proposed, which combines a tapered transmission line and 1-to-2 power dividers to realize a 1-to-4 power-dividing function. The simulated and measured results reveal a good agreement. The magnitudes of insertion loss are approximately equal, and phases are almost the same, so the proposed structure is used to design a passive spatial power combiner. The return loss of the spatial power combiner is below –15 dB on the whole, and insertion loss is between –0.9 ∼ 0 dB.

Wavelength division multiplexing light source with integrated quantum well tunable lasers and optical amplifiers

We describe a photonic integrated circuit composed of three 1.5 μm wavelength multiple quantum well tunable lasers with a passive optical power combiner and an optical output amplifier. Independent channel operation with 1–2 mW/channel output power is demonstrated.