Jean-Pierre Lanteri

Ultra wide band 24 GHz automotive radar front-end

The recent approval granted by the FCC for the use of Ultra Wide Band (UWB) signals for vehicular radar applications has provided a gateway for production of these sensors as early as in 2004. However, the rules governing the allowable spectral occupancy create significant constraints on the sensors operation. The implications for waveform design and the consequent limitation on system architecture, including antenna design and receiver architecture are discussed. Other practical considerations such as available semiconductor technology with low-cost plastic packaging are reviewed. This is developed into a methodology for developing a single board sensor with integrated antenna. Results are presented for a specification compliant antenna, and a low-cost plastic package for 24 GHz ICs. Finally, the required IC architecture for a transceiver is presented, along with measured results of a single-chip homodyne I/Q down-conversion receiver fabricated in SiGe.The recent approval granted by the FCC for the use of Ultra Wide Band (UWB) signals for vehicular radar applications has provided a gateway for production of these sensors as early as in 2004. However, the rules governing the allowable spectral occupancy create significant constraints on the operation of the sensors. The implications for waveform design and the consequent limitation on system architecture, including antenna design and receiver architecture are discussed. Other practical considerations such as available semiconductor technology with low-cost plastic packaging are reviewed. This is developed into a methodology for developing a single board sensor with integrated antenna. Results are presented for a specification compliant antenna, and a low-cost plastic package for 24GHz ICs. Finally, the required IC architecture for a Transceiver is presented, along with measured results of a single-chip homodyne I/Q down-conversion receiver fabricated in SiGe.

Multimode TRL and LRL calibrated measurements of differential devices

A multimode TRL (MTRL) calibration technique is discussed to characterize broadband differential devices. This algorithm has the advantage of using ground-signal-signal-ground (G-S-S-G) probes in the measurements without the frequency limitations of some other 4-port algorithms due to the coupling between the signal lines. Calibration standards and the issues associated with them are described. Practical issues of the underlying theory, such as assigning the calculated eigenvalues to the correct mode and to the propagation direction, have also been addressed and one case-specific solution is suggested. Also an MTRL algorithm has been adopted to avoid some of the difficulties of calibration structures with MTRL. Odd mode test results of differential active circuits with MTRL using G-S-S-G probes are shown to be consistent with the two port test results of the same devices using S-G probes.

A high power on-wafer pulsed active load pull system

An on-wafer load pull system that is capable of measuring load pull contours on true high-power and large-periphery devices is described. Measurements are made under low-duty-cycle pulsed DC and RF conditions to minimize the effects of heating due to power dissipation in the on-wafer environment. With the current implementation of the load pull system, any load impedance on the Smith chart can be presented to the output of 4-W devices. The system is fully error corrected for reflection coefficient, transmission coefficient, input power incident, input power delivered, and output power delivered. The system is capable of automatic control and measurement by means of an HP 9000 series workstation. Data taken on C-band MMIC (monolithic microwave integrated circuit) power amplifiers and 2-mm GaAs FETs are presented.<<ETX>>

A novel 100 MHz-40 GHz RF termination with bias network for optical systems

A novel wide-band DC-blocked MMIC RF termination with biasing network is presented. It provides return loss better than 18 dB from 100 MHz to 40 GHz. The main advantage of the design is that the DC blocking capacitor is placed directly on top of a wide grounding Si pedestal, thanks to M/A-COMs HMIC technology, reducing the ground inductance. At the RF side of the circuit, two 100-Ohm nichrome resistors have been put in parallel giving 50 Ohm. A small stub between the 100-Ohm resistors compensates for the inductance giving a very good match up to 40 GHz, Bond-wire pads have been designed on the chip and also on the host PCB to match the inductance of double wire-bond at the RF port.

Manufacturing test technologies for commercial GaAs RF/microwave integrated circuits

The unique requirements of a production test for commercial RF/microwave IC products are described. As product cost is one of the most significant discriminators in this marketplace, techniques for minimizing the impact of test on product cost are discussed, including test system hardware, software, test plans and automated device handling. To further illustrate the impact of these techniques an example of production test for a plastic packaged single pole double throw (SPDT) switch is presented.