摘要:
A circuit arrangement for obtaining an interference-free trigger signal such as for a fuel apportionment device from the ignition signal of an internal combustion engine, particularly one having a current-regulated final ignition stage. The output of the circuit arrangement begins when a signal derived from the final ignition stage exceeds a first, high threshold value and is terminated when, after falling below a second, low threshold value, a predetermined time lag period has ended. In this manner, a desired interference-free trigger signal is obtained which can be used to trigger various rpm-dependent circuit arrangements, such as electronic fuel apportionment and gear control.
摘要:
A transmission process with specific adaptive properties in an analog or mixed analog-digital transmission system, having a fixed base station and a number of subscriber station independent of one another. Information from the base station is transmitted to the subscriber stations wherein each information channel is converted by suppressed carrier, single-side band modulation to a narrow-band signal. The narrow-band signals are arranged spectrally adjacent one another in a frequency multiplex allocation scheme and are modulated on a carrier set at a higher frequency range using phase or frequency modulation. Each subscriber accesses no more than one of the information channels. Information transmissions from the subscriber stations to the base station is performed using narrow-band radio channels.
摘要:
A local ISDN transmission system has a central base station and a number of subscriber radio terminals greater than the number of communication channels. The system is connectable to subscriber ports through an S.sub.0 wireless transmission interface and is responsive to an activation request from a subscriber radio terminal for opening any available and free communication channel for a communication. An intermediate generator in the base station and in each subscriber terminal divides an ISDN two-wire subscriber connection line between a line termination section and a network termination section communicating by radio transmission. The intermediate generator, upon the occurrence of an activation request by a subscriber terminal, allocates a communication channel within waiting and monitoring periods for the activation of the ISDN two-wire subscriber connecting line. A delay system delays the activation request by a delay period sufficient to switch the allocated communication channel and activate a radio system of the subscriber terminal.
摘要:
A radio telephone system is disclosed to satisfy in the short term basic telecommunication needs of areas which are insufficiently or not yet covered. The system has a number of duplex radio channels (transmission channels) substantially smaller than the number of radio telephone subscribers. These transmission channels are connected to the ports of a telecommunications exchange system which is part of the stationary radio station and which ensures both incoming and outgoing traffic with the public telecommunications network and internal exchanges within the system. Signalling, exchange, management, servicing, and special functions of radio operation between the stationary radio station and the subscriber connection device are ensured by a radio switching device which uses one, or if required, several transmission channels used as organization channels and not connected to the ports of the telecommunications exchange system. In the organization channel, a constant time-multiplexed communication is maintained with the subscriber connection device according to a random access process based on a special organization channel protocol. An essential characteristic of the invention is that the subscriber connection devices have an a/b interface for the connection of telecommunication terminals. The system and in particular the organization channel protocol are designed in such a way that no differences from a wired telecommunications connection are perceptible to the user, although the system is radio operated.