Abstract: A method of testing an electric circuit and an arrangement for implementing the method are provided. The arrangement includes a current source connected to a network of electric components, the current source for supplying current to at least one current path of the network, the network being characterized with a predefined network configuration; a measurement unit connected to the network, the measurement unit for measuring effective values of node voltages in at least two nodes of the at least one current path, a node representing an equipotential point of adjacent electric components; and a processing unit connected to the measurement unit, the processing unit for deriving a characterizing value of at least one electric component of the network by using the effective value of current, the effective values of the node voltages, and the predefined network configuration.
Abstract: The invention relates to a method of performing channel simulation and a channel simulator. The channel simulation is performed digitally. At least a section of a signal (206) to be fed to simulation is transformed by convolution transformation from time space to transformation space in tansformation means (200) of the channel simulator. In weighting means (202), the transformed signal (208) is weighted by a channel impulse response that is transformed from time space to transformation space. Finally, the resulting signal (210) is inverse-transformed in inverse-transformation means (204) to time space.
Type:
Grant
Filed:
November 14, 2001
Date of Patent:
April 10, 2007
Assignee:
Elektrobit Oy
Inventors:
Juha Meinilä, Torsti Poutanen, Pertti Alapuranen
Abstract: A system, apparatuses, a method, and a computer program for producing signals for testing radio frequency communication devices are provided. The system comprises a non-real-time domain which includes a data generator for supplying a temporally discontinuous data stream which data stream includes signal waveform data and control data defining characteristics of a conversion from the signal waveform data into a radio frequency test signal. The temporally discontinuous data stream is fed into a transformer which transforms the temporally discontinuous data stream into a temporally continuous data stream, thus providing a transformation between the non-real-time domain and a real-time domain. The real-time domain includes a radio frequency unit which uses the temporally continuous signal data stream as input, and performs the conversion from the signal waveform data into the radio frequency test signal according to the control data.
Abstract: The invention relates to a linearization method and an amplifier arrangement for linearizing an amplifier (50) amplifying an RF signal with a variable envelope. The amplifier arrangement comprises a sampling device (20) for sampling an RF signal to be amplified. The amplifier arrangement further comprises a control device (30) arranged to generate, using samples, an output signal changing its value according to the envelope shape of the RF signal to be amplified. The amplifier arrangement further comprises an adjusting device (40) arranged to adjust, using the output signal, the bias current of the amplifier such that the magnitude of the output signal and the magnitude of the bias current change in the same direction.
Abstract: The invention relates to a method for automatic transmission power control in a transceiver suitable for a CDMA environment employing direct sequence diffusion. In accordance with the invention, a setpoint signal generated for automatic gain control of the receiver (RX) is used for amplitude or power (Po) control of the radio signal sent by the transmitter (TX).