Abstract: The connections of speakers in an automotive audio system are automatically checked during the assembly process to determine whether any speakers are shorted or have wires incorrectly connected to battery voltage or to ground. A signal diagnostic line can be used to indicate a plurality of different conditions. In addition, the actions of an audio limiting function can be monitored to detect shorts.

Abstract: A vehicular radio reception antenna is concealed within a body trim piece such as a spoiler or a luggage rack. A supporting body panel is utilized as a ground plane and a conductive loop is concealed within the trim piece. A transmission line connects two opposite sides of the resulting slot. Capacitors are used to connect the conducting loop to the sheet metal ground plane in order to form a dual slot/monopole antenna for receiving both FM and AM signals. An integrated mounting structure provides both mechanical and electrical connection of the trim piece and antenna in a single integrated assembly part.

Abstract: A predictive model is derived for subsequent use in a misfire detector in an internal combustion engine. Data collected using a test engine is curve-fitted using NARMAX techniques to obtain a computational formula for the predictive model which relates deviant acceleration at the accessible crankshaft section to deviant acceleration at the inaccessible crankshaft section. Thus, the model can be used during actual misfire detection to reduce the effects of the torsional oscillations.

Abstract: The remote entry system of an automotive vehicle is used to transfer remote control messages to an audio system thereby providing a low cost remote control feature for the audio system. In response to reception of uniquely coded RF control signals, the remote entry receiver communicates via a hard-wired communication link to the audio system causing the audio system to modify controlled audio system parameters in response to which pushbutton is activated on the remote transmitter. The remote entry system may interpret remote control signals differently depending upon the state of the ignition switch of the vehicle.

Abstract: A security system utilizing a key-mounted transponder achieves fast and accurate charging of the transponder by using a frequency search and acquisition phase which attempts partial charging pulses at a plurality of spaced frequencies. After a successful partial charging, a frequency calibration signal is received from the transponder which provides a reference in the transceiver for producing a pulse for fully charging the transponder. Frequency search and acquisition allows robust system operation while using low cost and low tolerance parts.

Abstract: A vehicle user can request emergency or roadside assistance from a response center by activating a button in the vehicle. The global positioning system is used to continuously store the vehicle location. A cellular telephone network is used to contact a response center and transfer a data string via modem containing information to assist the response center in acting on the request. Predetermined information concerning system operation is stored in a non-volatile memory during an activation for diagnostic purposes. Data is written in two groups at respective times during an activation, and a status flag indicates whether both groups were successfully written to memory.

Abstract: Irregularities in crankshaft velocity introduced when measuring crankshaft rotation at a section of a crankshaft in an internal combustion engine that is less damped to torsional oscillations than is another more accessible crankshaft section are corrected using a NARMAX-generated model to predict rotation measurements that would have been obtained at the inaccessible section based on data actually collected at the accessible crankshaft section. Thus, the effects of torsional oscillations in the crankshaft are substantially filtered away, resulting in crankshaft acceleration values that form the basis of a misfire detector having nearly maximum signal-to-noise performance.

Abstract: A dual-band radio receiver utilizes a single transformer to provide impedance matching between signal mixers from separate signal paths to their respective intermediate frequency filters. Thus, a dual-band radio receiver can be made eliminating one transformer and the printed circuit board space of one transformer. In addition, only one transformer needs to be frequency aligned or adjusted during manufacturing.

Abstract: A button system for the control panel of an automotive audio system is adapted to curved bezel shapes wherein push buttons are non-coplanar. Each button operates normal to the bezel surface at the button location. The button system interfaces with a flat elastomeric membrane switch pad.

Abstract: An FM radio receiver, particularly for mobile receivers, reduces the effects of multipath distortion. It selects either an adaptive process (constant modulus algorithm or CMA) or a antenna diversity process depending on the circumstances of the instantaneous reception. The receiver reduces both the decline of the level of received signals with the diversity process and waveform distortion with the CMA process.

Abstract: A security system for an automotive vehicle having an engine is operatively connected between engine running electrical components that are connected to an electrical power source and a lock switch having at least two operative positions. The security system has a key with a memory device carried thereon with a first security code stored in the memory device. A theft control module having a memory storing a second security code is operatively connected between the switch and the engine running electrical devices. The theft control module operates to first permit the engine running electrical components to enable the starting of the engine and then to compare the first and second security codes. Before starting the engine, a counter is compared to a predetermined number so that the engine starting is limited to only a predetermined number of attempts. The engine is disabled if the number of attempts exceeds the predetermined number.

Abstract: Irregularities in crankshaft velocity introduced when measuring crankshaft rotation at a section of a crankshaft in an internal combustion engine that is less damped to torsional oscillations than is another more accessible crankshaft section are corrected by performing a nonlinear transformation via a neural network to predict rotation measurements that would have been obtained at the inaccessible section from data actually collected at the accessible crankshaft section. Thus, the effects of torsional oscillations in the crankshaft are substantially filtered away, resulting in crankshaft acceleration values that form the basis of a misfire detector having nearly maximum signal-to-noise performance.

Abstract: An AM-modulated carrier signal is converted to a lower carrier frequency through mixing with a square wave local oscillator signal. A field-effect transistor chops the modulated signal according to the square wave signal so that a chopped or sampled version of the modulated signal is created without passing the signal through a semiconductor junction. A filter then selects the desired mixing product. Thus, a distortion free mixing of the signal is obtained using low cost components including a JFET switch and a square wave output from a microcontroller.

Abstract: A vehicle user can request emergency or roadside assistance from a response center by activating a button in the vehicle. The global positioning system is used to continuously store the vehicle location. A cellular telephone network is used to contact a response center and transfer a data string via modem containing information to assist the response center in acting on the request. The vehicle installed system initiates an automatic call-in to the response center if the elapsed time since the last successful connection with the response center is greater than a predetermined time. Data is transmitted during the automatic call-in that identifies the vehicle and verifies to the response center that a particular system is operative.

Abstract: A vehicle user can request emergency or roadside assistance from a response center by activating a button in the vehicle. The global positioning system is used to continuously store the vehicle location. A cellular telephone network is used to contact a response center and transfer a data string via modem containing information to assist the response center in acting on the request. The response center sends a termination tone to the vehicle upon satisfactory completion of the request. If the vehicle loses contact with the response center prior to receiving the termination tone, it attempts to reestablish communication with the response center.

Abstract: A cassette tape transport mechanism is provided with a mechanism for quickly detecting the stoppage of a take-up reel, thereby causing a tape direction change cycle to be initiated before a significant amount of tape can form a jam during a tape eating condition. The number of tape direction changes within a predetermined time is also counted and compared to a reference limit to detect a tape eating malfunction. The tape may be automatically ejected and an error message sent to the taper player display, allowing the user to clean the cassette or the player mechanism to remove sticky substances that may be causing the tape eating condition.

Abstract: A multiband antenna for mounting on glass for an automotive vehicle window is disposed around the periphery of the window to provide a long length for the AM antenna. A series capacitor decouples one end of the AM monopole antenna from ground. The capacitive element acts as a short circuit at FM frequencies to facilitate operation of the antenna as a dipole for FM signals. A pair of inductive elements is connected in series with the antenna radiating element to effectively trim the length of the antenna to a resonant length for FM frequencies.

Abstract: A vehicular radio reception antenna is concealed within a body trim piece such as a spoiler or a luggage rack. A supporting body panel is utilized as a ground plane and a conductive loop is concealed within the trim piece. A transmission line connects two opposite sides of the resulting slot. Capacitors are used to connect the conducting loop to the sheet metal ground plane in order to form a dual slot/monopole antenna for receiving both FM and AM signals.