Abstract:
A suitable diffusion nozzle (20) for an ultrasounds probe using water as coupling agent between a piece under inspection and an acoustic transductor (13) such that the water is driven towards the surface of the material through a propulsion channel (21) surrounded by a plurality of diffusion channels (23) through which air is injected under pressure, forming an insulating screen capable of repelling the drops of water generated on the jet of water striking the surface of the material.
Abstract:
The embodiments of the present invention relate to a method in a transmitting unit; a method in a receiving unit; a transmitting unit and a receiving unit, in a wireless communication network employing Time Division Multiple Access, TDMA, for transmitting and, receiving and demodulating data, respectively, the data being transmitted in a signal comprising a burst, wherein bursts relating to NMS number of mobile stations are multiplexed into a single time slot. The transmission comprises grouping a block of N b number of user code bits, representing the data to be transmitted, into NDS/NMS groups of user code bits. Mapping the groups of user code bits to data symbols such that one group is represented by one data symbol, thereby obtaining a block of data symbols, wherein each data symbol is drawn from one or more pre-defined complex-valued symbol constellation(s). The transmission further comprises repeating the block of data symbols, such that the burst to be transmitted comprises NMS number of equal blocks of data symbols, rotating the NMS number of blocks of data symbols according to a mobile-station-specific rotation, and transmitting the rotated blocks of data symbols in a burst in the time slot.
Abstract:
Non-linear distortions, called glitches, occur in radio receivers when automatic gain control (AGC) is employed for regulating the dynamic range of the received signal. It is proposed to determine (S1) the occurrence of a glitch caused by operation of the AGC mechanism, and estimate (S2) a representation of how energy of a signal transient associated with the glitch is transferred by digital filter(s) in the receiver. The radio signal is then detected (S3) at least partly based on the estimated representation. In this way, the adverse effects of the glitch can be mitigated and detection of the desired signal can be significantly improved. This also means that the link performance will be significantly improved.
Abstract:
The invention relates to a method for transmitting call data in a digital wireless communication network, said call data being transmitted over at least one radio frequency channel in a sequence of timeslots. Call data are transmitted in the network using timeslot hopping in which the call data of each user of the network are transmitted with a different timeslot hopping sequence.
Abstract:
In a radio transmission scheme reusing slots such as by using Orthogonal Sub Channels (OSC) in the downlink channel a parameterized, hybrid quaternary modulation is employed. In the hybrid quadrature modulation, the symbol constellation is in quadrature, with the 4 symbols lying on the unit circle in the complex plane. The orthogonality of the 1 and Q branches is preserved. A cross power branch ratio parameter α is introduced, allowing the total energy of the signal to be divided unequally between the two sub channels. This parameter α may be changed from over time.
Abstract:
In a radio system node, such as a Base Transceiver Station (BTS), a compensation unit is provided to convert information about downlink signal strength in a measurement report received from a mobile station when the signal to the mobile station is transmitted using several co-channel signals transmitted simultaneously in the same time slot and at the same frequency.
Abstract:
In a method, modulator, transmitter and receiver, the modulator of data signals to be transmitted simultaneously to at least two receiving mobile stations in the same transmission time slot is adapted to select rotational angle of a QPSK transmission modulation, such as a hybrid α-QPSK modulation used to modulate the data signals to the at least two mobile stations in response to the capabilities of the mobile stations that share the same transmission slot.