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The automotive environment with its wide range of temperatures and corrosive liquids and gases provides a harsh environment for electronic systems. This situation is further compounded by the fact that these systems are composed of a wide variety of dissimilar materials. It should be no surprise, therefore, that corrosion can be a significant problem in electronic systems. This paper will discuss corrosion problems related to the following: open circuits in connector contacts, leakage and shorts on printed circuit boards, metal migration problems, and corrosion problems in plastic encapsulated semiconductor devices. In many of these corrosion situations, the initial mechanism involved in the corrosion process will often cause an electronic system to malfunction. It is, therefore, of utmost importance that these corrosion mechanisms be carefully evaluated during the development of electronic systems so that necessary steps can be taken to prevent their occurrence.

The European Broadcasting Union has for about 10 years been studying the development of a radio-data system for FM broadcasting. This system will facilitate the introduction of automatic tuning features in new domestic, portable and car radios, and will additionally permit the distribution of auxiliary information within a wide range of applications. After a brief description of the general system requirements, some specific problems relating to reception in moving vehicles, particularly under severe multipath conditions, are discussed. The coordinated applications of the system are then reviewed, and special mention is made of the radio-frequency and baseband-modulation characteristics, chosen to implement these coordinated applications with a maximum of flexibility. Finally certain possibilities for the design of receivers are indicated as well.

While recent developments in manufacturing and component technology facilitate the packaging of a basic radio circuit design flexible enough to take into account worldwide markets, many unique and sometimes seemingly superficial specifications stand in the way of a truly “universal” or World Radio chassis. Although somewhat technical in subject matter, this paper does not attempt to address solutions to the problems; rather, it highlights what concerns must be solved before a truly World Radio is achieved.

In the past decade, the high frequency response of automotive tape playback equipment has been extended, the efficiency of loudspeakers has increased and the cost of high power amplifiers has been reduced. Consequently, tape noise can be a significant problem when listening in the car. This paper discusses the design philosophy of the Dolby B-type and C-type noise reduction systems that are now widely used throughout the in-car entertainment industry to overcome the tape noise problem. Information relating to basic tape parameters, to other approaches to noise reduction and to noise reduction system defects is also included.

INFORMATION ON TRAFFIC PROBLEMS is transmitted by many radio stations as part of their regular programs. The problem for the motorist is that his car radio must be tuned to the right station, and that he must listen constantly to the program of that station. He cannot even play a cassette. FM stations using the ARI system transmit inaudible signals that 1) help to identify the station, and the area for which traffic bulletins are transmitted, or even tune the car radio automatically to that station 2) turn up the volume of the receiver during the traffic message to a preset level to ensure that the message is heard 3) stop the cassette play, switch over to the traffic bulletin, and switch back to cassette after the message. Due to simplicity, efficiency and low cost the ARI system has been very successful over the last ten years. Virtually every car radio sold in the ARI countries Germany, Austria, Switzerland, Luxembourg in the past 5 years was equipped with an ARI decoder.

THIS PAPER describes a design guide for a driving Integrated Circuit (IC) of a Liquid Crystal Display (LCD) for automotive application. Many LCD Driver ICs are now available at market places, however, most of the ICs are not very suitable to advanced automotive LCD. This paper describes important parameters of both LCD and its driving IC to optimize display performances.

The lecture deals with the special conditions that have to be taken into account in the steering of large articultated vehicles, for example the control of oil flow, positive and negative control forces. The systems that are used today are described and their advantages and disadvantages outlined. Examples of systems are hydraulic/mechanical and hydrostatic steering. Under subject of hydrostatic steering, the Flow amplifier system is dealt with in detail.

The GEOSTAR Satellite System, now in development, will provide accurate positioning and two-way message capability for subscribers equipped with compact, inexpensive transceivers. The full GEOSTAR Satellite System is scheduled for operation by 1987. The GEOSTAR Satellite System, now in development, will provide accurate positioning and two-way message capability for subscribers equipped with compact, inexpensive tranceivers. Positions are displayed at the transceiver and, if desired, at a central dispatch facility. Messages, in the form of short telegrams, can be exchanged in both directions between any two subscribers or between a subscriber and a central dispatch facility. All positioning and message services are provided by a redundant set of computers at the GEOSTAR ground station. Three GEOSTAR satellites relay signals between the GEOSTAR ground station and user transceivers anywhere in the continental United States.

The history of the automobile's progress is one of harmony with society. Automobiles have progressed by applying to the maximum degree the available technologies of each era and seeking harmony between social needs, the needs of consumers and the state of road system development. The most critical and lasting issues in the automobile world will continue to be safety, the wise use of natural resources and protection of the environment. While it is necessary for automobiles to make their own contribution to the solution of these issues, it is also vital that automobiles be developed as a part of a total system in harmony with public investment, such as road facilities. In particular, it is necessary that a radio communications link between automobiles and a traffic control network be introduced to enable driving that is safe, efficient and in good harmony with the environment.

This paper describes a diversity receiving system for car radios which effectively reduces distortion caused by multipath propagation. The system consists of two antennas connected to FM receiving units, distortion sensing logic circuits, a stereo multiplexer, and a stereo amplifier. The input of the stereo multiplexer is switched between the two FM receiving units upon command from the distortion sensing logic circuits. One advantage of this system is that the distortion sensor allows the output level to correspond to auditory perception, thus assuring accurate selection between the two antennas. The effectiveness of diversity selection in reducing multipath distortion has been confirmed in a simulation experiment which was performed using distortion sensor output data that were recorded in a field trial. An instantaneous high-cut control function for the audio signal is also incorporated into the system to eliminate any distortion that remains after diversity selection is performed.

A successful development was achieved of a car radio with an electronic tuning system which is provided with such an entirely novel function as continuous automatic selection of the broadcasting station with the highest receiving level among identical programs by directly comparing the receiving sound signals of the broadcasting station with those of other stations. It is particularly epoch-making that this development was realized with a 1-tuner system, since it was thought very difficult to achieve such a development with a 1-tuner system. The practical value of this development could be also confirmed.

Mobile radio telephone equipment must be properly installed in a vehicle if trouble-free and convenient operation is to be achieved. Adequate provisions by vehicle manufacturers must be made to ensure installations are simple, foolproof and free from potential sources of interference. This paper also describes the possibility of interfacing the radio telephone to the vehicle control and display unit where this is appropriate.

The advantage of using the heater conductors of an automobile backlite as a broadcast receiving antenna, as compared to the use of a conventional telescopic whip, include reductions in damage, corrosion, aerodynamic drag and manufacurers’ costs. The paper develops an approach to the design of backlite antenna systems aimed at maximising the receiver signal input by attention to the form and position of the heater conductors and by minimising the deleterious effects of the feeder cable to the radio. Adequate levels of signal are shown to be available at lf, mf and vhf. To optimise performance, a buffer amplifier is used at lf and mf and the antenna is matched to a low-noise amplifier at vhf. Test results for sedan, hatchback and station wagon vehicles presented show very acceptable performance, in many cases better than those of conventional whip antennas.

High-performance vehicular entertainment systems are employing ever-higher-power audio amplifiers, with attendant heat-dissipation requirements. One solution to this problem is the two-state switching amplifier, which reduces thermal loads by 60% in a 12-volt system. Heat and size considerations causing selection of this approach are discussed. A feedback-controlled modulation technique with high loop gain is employed. Power supply rejection and distortion requirements are met. RFI suppression techniques including shielding and spectrum spreading are required. Final performance achievement and limitations are reviewed.

The increasing availability of digital tuning systems using phase-locked loops to control the radio local oscillator (LO) frequency and RF tuning, and the anticipated introduction of an AM stereo broadcast service, has motivated the development of a new set of integrated circuits (I/Cs) specifically designed to handle the broadcast signal processing functions of the radio. Features such as a valid station stop detector are provided for interfacing with the tuning system and improved FM performance is achieved, together with the use of dual-threshold AGC circuits and a novel, low-distortion quadrature detector. Special attention has been paid to the AM circuit design in order to accommodate the proposed AM stereo broadcast formats and a new decoder circuit has been developed to complement the improved performance obtainable with this I/C set.

Ford Motor Company is pursuing quantitative techniques in the identification and resolution of entertainment system electromagnetic interference (EMI). A radio frequency (RF) anechoic chamber provides shielding from external electromagnetic noise sources and minimizes measurement errors due to voltage standing waves in the room at high frequencies. Computerized radio frequency measuring equipment provides reports summarizing vehicle radiated emission data, tests data relative to radio system RF noise tolerance limits and documents emission attenuation following addition of EMI shielding and/or filtering.

This paper develops a thermal model for analyzing transient and steady state heat flow in power amplifier heat sinks. This model is used to predict I.C. junction and heat sink temperatures, power output, and power dissipation over any time interval. Methods of determining heat sink parameters are discussed followed by a comparison of measured versus calculated data on a two channel power amplifier.

The subject of research into truck accidents with a view to making safety modifications to trucks is steadily gaining in importance. In the light of newly compiled truck accident material comprising 2000 cases from 1979 to 1983 the problem of truck accidents can be assessed comprehensively. This study covers truck accidents with pedestrians, bicycles and motorcycles, cars, truck/truck collisions and single-truck accidents. Because all accident groups and their percentage weighting according to real life are considered, it is possible to transfer the results to the general accident occurrence. The internal structure of the accident groups is contrasted with the official accident statistics in significant accident parameters. The frequencies of essential parameters, i.e. the kind of collision, the type of accident and the risk for the truck occupants and the other traffic participants involved are indicated.

Radar Altimeters are being included in several existing Air Force aircraft. Of these, the A-10, F-15, and the F-16 are also envisioned to perform the night, under the weather attack mission. This mission, coupled with limited available cockpit space and the anticipated high pilot workload has led to a design effort to include the radar altimeter on the HUD. The LANTIRN system offered a key opportunity to accomplish this HUD integration. The design has evolved from pilot opinions through simulation and now flight test. Plans are currently being made to conduct a simulation to make minor changes to the display based on test results to further optimize the display. This radar altimeter design and particularly the way the design has evolved should serve as examples for future efforts. Of particular note is that this display has been designed from the beginning for a specific purpose and is being optimized for its intended operational environment and the pilots who will use it.

Efficient integration of the functions of communications, radio navigation and cooperative identification (CNI) will provide significant improvement in both combined and single function availability, while providing the flexibility to adapt to changing mission requirements. This improvement is achieved by providing increased levels of commonality and connectivity among the processing elements, maintained by the distribution of the terminal control and built-in-test. Advances in technology, such as RF-LSI, VHSIC and high power semiconductor development has led to accompanying advances in receiver, processor and transmitter design, respectively, that make realizable the processing modular elements necessary for the required architectures. Since the CNI waveform performance is dictated by interoperability, the power of these new technologies must be applied to flexible and “broadband” modules to process the waveforms.