Tag Archives: Microwave

Teardown and experiments with a Doppler microwave transceiver

Kerry Wong did a teardown of Microsemi’s C900502 X-band planar transceiver:

I got a couple of Microsemi’s C900502 10.525 GHz X-band Doppler radar motion sensors a while ago. This batch was made in UK and had “UK patents 2243495 and/or 2253108 apply” printed on the case. I have seen a teardown of an HB100 Doppler radar module before and was wondering if I this one is any different inside.

Teardown and experiments with a Doppler microwave transceiver – [Link]

On-Chip Microwave Laser

Lasers are everywhere these days: at the checkout in the supermarket, in the CD player in the lounge – and quantum researchers need them to test qubits in the (future) quantum computers. For most applications, today’s large, inefficient lasers are a perfectly adequate solution, but quantum systems operate on a very small scale and at extremely low temperatures. Researchers, for the past 40 years, have been trying to develop accurate and efficient microwave lasers that will not disturb the ultra-cold and fragile quantum experiments. A team of researchers from the Dutch Technical University Delft have now developed an on-chip laser, which is based on the Josephson-effect. The resulting microwave laser opens the door to applications where microwave radiation with a low loss is essential. An important example is the control of qubits in a scalable quantum computer.

Lasers emit coherent light: the line width (the color spectrum) can be very narrow. A typical laser comprises a large number of emitters (atoms, molecules or charge carriers in semiconductors) in a oscillator cavity. These conventional lasers are generally inefficient and generate much heat. This makes them a challenge to use in low-temperature applications, such as quantum technologies.

The researchers constructed a single Josephson junction in an extremely small superconducting oscillator cavity. Here, the Josephson junction behaves like a single atom, while the micro cavity behaves like a pair of mirrors for microwave light: the result is a microwave laser on a chip. By cooling the chip down to ultra-low temperatures (less than 1 kelvin) a coherent beam of microwave light is generated at the output of the oscillator cavity. The on-chip laser is extremely efficient: it requires less than one picowatt to produce laser radiation.

The research paper can be read here.

Source: Elektor

Teardown and analysis of microwave (26.5GHz) electro-mechanical step attenuators

Teardown and analysis of microwave (26.5GHz) electro-mechanical step attenuators from The Signal Path:

In this short episode Shahriar takes a close look at a pair of Hewlett Packard microwave electro-mechanical step attenuators operating up to 26.5GHz. Mechanical attenuators offer excellent repeatability, low insertion loss and nearly limitless linearity. The teardown reveals that the construction of both modules is very similar on the microwave path. In fact, the lower-frequency model still uses the same attenuator components. The newer model employs electronic control circuity while the older generation attenuator uses purely mechanically controlled DC path. Both models use a solenoid style actuators for step attenuation control.

Teardown and analysis of microwave (26.5GHz) electro-mechanical step attenuators – [Link]