Denver Humphrey

A 24GHz Low-Cost, Long-Range, Narrow-Band, Monopulse Radar Front End System for Automotive ACC Applications

This paper presents details and results of the development of a low-cost, narrow-band, long range radar (LRR) front end system at 24 GHz, intended for autonomous cruise control (ACC) and other medium and long-range automotive applications. The system uses a high directivity patch array Tx/Rx antenna and a low-cost, high sensitivity RF front end. The narrow band, pulse radar concept is well suited for the applications envisaged, avoiding at the same time some well known regulatory issues related with existing UWB short range systems. The accurate azimuth detection functionality has been implemented by employing a phase/amplitude comparison monopulse solution using a dual receive patch-array antenna. Key performances currently achieved with the new system include: range detection of up to 120 meters for regular car size targets, azimuth detection range of plusmn 8deg, with azimuth accuracy better than 0.3deg. The successful realization of such low-cost, long range radar system at 24 GHz could potentially lead to two important developments in the near future: the implementation of the new radar technologies into the lower class, high volume car market and challenging the dominance of the much more expensive ACC systems currently developed at 77 GHz.

An LTCC design technique based on accurate component models and EM simulations

This paper describes the LTCC design methodology adopted by TDK. The main aim of the new method is to reduce the number of sample iterations for mobile communication front-end modules. The main elements of the method include, extracting accurate component models, incorporating into the models an automated layout generation facility and linking the layout to an EM simulator for final analysis. The component models discussed include equivalent circuits, EM generated databases and neural network models. Models up to 18GHz have been produced and verified by measurements. The influence of manufacturing process tolerances have been studied and incorporated into the models. Unwanted coupling mechanisms are discussed and examples of the coupling levels between surface pads and embedded components are presented for the first time. The predicted and measured results of a GSM/DCS antenna switch module are presented. The agreement between the predicted response and the measured response is excellent.

Planar Antenna Design for Long Range Radar Applications

This paper describes the design of a high gain planar antenna on lossy substrate for use in long range radar applications in the 24GHz ISM band. This is significant since most current vehicle radars operate in the 77GHz frequency band, but as technologies for lower frequencies are less, the system should be cheaper. The paper discusses requirement in the design evolution from prototype to integrated system and uses the overall radar cost as a design parameter. Lastly measured results are presented and an indication of how the design is incorporated into the overall system is given.