Richard Alan Anderson

A fully integrated 24 GHz SiGe receiver chip in a low-cost QFN plastic package

A fully integrated, plastic packaged, 24 GHz SiGe receiver chip is presented. The chip has been manufactured using a commercially available SiGe foundry process. It can be used in a variety of applications including automotive radar sensors and phased-array receivers. The receiver supports two channels which can be used to support sum and delta antenna pattern inputs. The receiver comprises of two LNAs, a DPST switch, an I/Q downconverter, baseband variable gain amplifiers, and integrate-and-dump filters. The receiver has 45 dB of conversion gain with 7.8 dB noise figure (with plastic package) at 24 GHz

Periodic filters for performance enhancement of millimeter-wave microstrip antenna arrays

In this paper, periodic filters have been employed to enhance the performance of microstrip antenna arrays in automotive radar sensors. An isolation of more than 45 dB has been measured between transmit and receive antenna arrays formed on the same substrate with a separation distance of only 40 mm between them. The isolation enhancement obtained is more than 15 dB. Also a gain enhancement of about 2 dB has been observed due to employment of these periodic filters. Since these periodic filters consist of circular openings etched on the ground plane of the antenna, there is no additional cost or fabrication effort associated with this technique. These openings act as periodic stop band filters to suppress surface waves propagating between the antenna arrays. Measured and computed isolation values agree well.

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.