Abstract: The invention is based on a method for finding an Internet or E-mail address. Internet or E-mail addresses are noted in the content of many teletext pages regardless of whether they contain advertising or information. The addresses are currently transmitted within the visible area of a teletext page so that the user must normally copy them and enter them into an Internet browser. The invention is based on the object of creating a simplified method for finding an Internet or E-mail address. The method according to the invention for finding an Internet or E-mail address which is reproduced in a teletext system, comprising visible areas and non-visible areas of the teletext system, a selection unit, a control unit and a link unit, is distinguished by the fact that the address in the visible area is selected by the selection unit, the control unit recognizes the selected address, the control unit accepts and/or modifies the address format and the address is selected via the link unit.

Abstract: The invention relates to a method for converting a digital signal an analogue signal and to a digital to analogue converter comprising means for converting a digital signal to a thermometer coded signal, means for randomizing the thermometer coded signal, means for controlling the means for randomizing based on the digital signal and means for converting the randomized signal to analogue.

Abstract: The invention relates to a method for calculating a least mean square algorithm using an N-tap filter. A modified least mean square algorithm is used for the calculation. In a first calculation step, calculation is effected using a first, wide bit width in the N taps. In a second step, depending on the result of the first calculation step, a second, smaller number of bits is selected for the further method steps.

Abstract: The invention relates to a data processing device for recovering digital data which is received in an analogue transmitted signal. According to the invention, the received signal is digitized and a threshold is determined in a threshold estimator. The interference in the channel is corrected in a downstream adaptive equalizer, and a bit clock generator produces the correct sampling rate and phase for the data of a line. The threshold estimator is used to determine the mean value of an input signal for each line, and this value is then taken as the optimum decision value for sampling the data bits for this line. By using an adaptive equalizer, it is possible to correct different types of distortion, caused by the transmission channel, without the need for a training signal. The data processing device according to the invention can thus be used universally for all digital additional signals occurring in a television signal, for example.

Abstract: The invention relates to a method for converting a digital signal an analogue signal and to a digital to analogue converter comprising means for converting a digital signal to a thermometer coded signal, means for randomising the thermometer coded signal, means for controlling the means for randomising based on the digital signal and means for converting the randomised signal to analogue.

Abstract: For the acquisition of multistandard video data a decoder is used with a register 201 having 24 cells for storing 3 times 8 bit of data. Each of the three bytes are connected with logical devices in order to compare the content of the cells with given start codes. Start of the register 202 is byte3, followed by byte2 and byte 1. In addition a second 8 bit register 202 is connected in parallel to the register 201. The content of byte3 is also fed to a Hamming (8/4) decoder 203 and of byte2 to a Hamming (8/4) decoder 204. Each decoder output of 4 bits is fed to the assigned 4 bits of the register 202, respectively.

Abstract: A method for recovering a video signal uses an adaptive equalizer, the characteristics of which are adjusted to the conditions of a transmission channel by using the digital data signals that are concomitantly transmitted in addition to the analogue signal components in a video signal. This adjustment is then used for analogue signal components of the video signals. A teletext signal can advantageously be used for the adjustment.

Abstract: The key component of a digital PAL or NTSC color decoder is a quadrature demodulator for these AM modulated signals. For a SECAM color decoder, however, an FM demodulation is required which is conventionally implemented using a Hilbert filter which is followed by a CORDIC processor and a differentiation stage. It would be advantageous if for multi-standard applications a general-purpose color demodulator for PAL, NTSC and SECAM systems could be implemented on one chip having as much as possible common demodulation processing stages. According to the invention a single common quadrature mixer is used for all three color systems. A resulting bias effect caused by the use of a single mixing frequency is corrected in a clamping stage. The bias effect can also be used for line identification.