Abstract: The invention provides a method and a communication device for cancelling echoes in the communication device, comprising: receiving path means and sending path means for receiving and sending respective signals, and echo compensating means for generating an echo control signal which is representative of a perceived echo, which echo compensating means are coupled between the sending and the receiving path means, and comprise an echo digital control signal generating means, and a digital-to-analog convertor coupled to the digital control signal generating means and to the receiving path means. Hardware and software implementation are easy and the dynamic range of an analog-to-digital convertor present in the receiving path is limited.

Abstract: A battery-operated communications device has a radio frequency part, a baseband processing arrangement, a timing control arrangement, a continuously running reference clock that is coupled to the timing control arrangement, and a clock frequency reduction means. The timing control arrangement is partitioned into a logic block that has synchronization means, for, during a reduced power stand-by mode of the communications device, maintaining synchronization with respect to a radio base station. The clock frequency reduction means generates a derived clock signal that has a frequency lower than a clock frequency of the reference clock oscillator. The derived clock signal controls the logic block during the reduced power stand-by mode.

Abstract: An oscillator in an integrated circuit in which the oscillator signal is taken from the output of a comparator, and the decision level of the comparator is determined by the voltage difference between the input of the comparator and the substrate of the integrated circuit. Interference voltages on the substrate, caused by other circuitry on the integrated circuit, are compensated with equal interference voltages at the input of the comparator. To effect this compensation, a capacitor is connected between the input of the comparator and the substrate, in lieu of the conventional capacitor that is connected between the input of the comparator and a ground potential.