Abstract:
A coder for segmented coding of an input signal (b) by using of a controllable quantizer (1C) and a buffer memory (6) is described. Data of the input signing (b), which are quantized and VLC-coded in operation, are buffered in the buffered memory (6). To avoid the conventional control, beset with drawbacks, of the quantizer (1C) by using of the filling state of the buffer memory (6), a controller (3, 4, 7, S1, S2, S3) provided with which a single adjustment of the quantizer (1C) for a signal segment to be coded is determined in that the signal segment is trial-coded at different adjustments of the quantizer (1C), the bit volume (the number of bits) is determined at each trial run, resulting in a VLC coding of the signal segment at the actually selected adjustment of the quantizer (1C), and that adjustment of the quantizer (1C) is used for the final coding and transmission of the signal segment which, during the trial runs, has yielded a bit volume which substantially corresponds to a nominal bit volume.
Abstract:
In an access control system (8)--which comprises a transponder communication device (9) and at least two transmission coils (11, 12) connected to the transponder communication device (9), for receiving transponder signals, of which a first transmission coil (11) is associated with a first door (2), and which comprises a first activation device (18 associated with the first transmission coil (11) and the first door (12), and which comprises a first door opener (23) for the first door (2) and a logic device (45) for activating the first door opener (23)--the two transmission coils (11, 12) have arbitrarily large receiving ranges and the first transmission coil (11) and at least one further transmission coil (12) are followed by amplitude detector (34, 36) by which the amplitudes of the transponder signals supplied by the two transmission coils (11, 12) can be detected and the logic device is arranged after the amplitude detector (34, 36) and adapted to detect a condition in which the amplitude of the transponder signal supplied by the first transmission coil (11) is greater than the amplitude supplied by the second transmission coil (12), which first door opener (23) for the first door (2) can be activated the logic device (45) only upon detection of this condition.
Abstract:
A radio frequency level control circuit is disclosed having a level controller, a sensor and a variable gain amplifier which are located in a feedback path of the level controller. The level controller forms an output signal by mixing an input signal and a feedback signal in a Gilbert cell. The sensor forms a measuring signal and a reference signal from the output signal. The variable gain amplifier produces a feedback signal from a difference between the measuring signal and the reference signal. The Gilbert cell has a current mirror circuit which is configured to lower the supply voltage of the Gilbert cell and to reflect current from the first stage to the second stage. The current mirror circuit is located between a first stage and a second stage of the Gilbert cell, where the first stage is coupled to the feedback signal and the second stage is coupled to the input signal.
Abstract:
In an arithmetic encoder and/or a corresponding arithmetic decoder, an A parameter, related to the size of a value interval, is truncated prior to multiplying the A parameter times the probability of a symbol, and the carry-over of the multiplication is controlled in the re-normalizing step in the encoder or decoder.
Abstract:
A DC/DC converter of the flyback/forward converter type includes a switch (S), a transformer (T), a first diode (D1), a first capacitor (C1), a second diode (D2) and a second capacitor (C2). The first and the second capacitor are arranged in series between the output terminals (K3, K4) of the DC/DC converter. The DC/DC converter has a high efficiency and is very suitable for operating a lamp with a DC current.
Abstract:
A communication system is composed of a terminal unit (1) which includes a control circuit (5) and at least two non-volatile rewritable memories (6, 7) for storing software, and a station (2) for supplying new version software to the terminal unit to replace old version software currently stored in the two memories. The station has a control circuit (5) which is configured for exchanging software contained in at least one memory (6, 7) of the station in response to an exchange command. The software includes at least first and second blocks which are stored each in a different non-volatile memory (6, 7) of the terminal, the first software block containing specific functions for use during an exchange operation, and the second block not containing specific functions for use during an exchange operation. During an exchange operation the control circuit (5) of the terminal is configured for replacing a stored old version second software block with a received new version first software block, and thereafter replacing a stored old version first software block by a received new version second software block.
Abstract:
A method and an arrangement for generating a composite video signal in accordance with the chroma-key method in which a virtual background spill signal is generated and added to the composite video signal to avoid darkening effects which are produced when eliminating spill light, and to eliminate brightening effects which are produced in "clean-up" operations. The background spill signal may consist of the product of a virtual spill signal source (SP) and a control signal (k.sub.3). The control signal (k.sub.3) is preferably the difference between a foreground control signal (k.sub.1) and a background control signal (k.sub.2), and both signals should be identical in the foreground and background ranges but different in spill ranges.
Abstract:
A scanner for line-sequentially scanning a film frame by means of linear image sensors in which the charges of the light-sensitive pixels (1) are transferred to two shift registers (4, 5). To enhance the horizontal resolution in the picture display, the outputs of the two shift registers are line-sequentially and alternately connected (10) to the common input of the subsequent signal--processing channel for generating a progressive quincunx structure of the line-sequential pixel charges.
Abstract:
A discharge vessel with a ceramic wall encloses a discharge space in which besides a rare gas also an ionizable filling comprising at least NaI is present. Two electrodes having tips with a mutual distance EA are arranged in the discharge space which discharge vessel has an internal diameter Di over at least the electrode distance EA. The discharge space is Hg-free and the ionizable filling further comprises Zn and the electrode distance EA and the internal diameter Di comply with the relation 1.ltoreq.EA/Di.ltoreq.4.
Abstract translation:具有陶瓷壁的放电容器包围放电空间,其中除了稀有气体之外,还存在至少包含NaI的可电离填充物。 具有相互距离EA的尖端的两个电极布置在放电空间中,放电室至少具有电极距离EA的内径Di。 放电空间是无汞的,可电离填充物还包含Zn,电极距离EA和内径Di符合关系1 = EA / Di 4。