摘要:
A reception method and a receiver in a cellular radio system, the receiver comprising means for measuring the power level of each received signal. To detect the received signal in an advantageous manner, the receiver of the invention comprises means for dividing the received signals into several groups having at least two signals each, and means for detecting the signals in each groups from the received transmission simultaneously.
摘要:
The invention relates to a reception method and a receiver comprising means where a received signal is sampled, and means where the mutual delays of the transmissions contained in the signal and the strengths of the transmissions are measured from the received signal, said transmissions originating in one or more transmitters. In order to ensure reception of high quality, the receiver according to the invention comprises means, the input of which, is the sampled signal, and in which an estimate is calculated from the samples for each desired transmission on the basis of all samples which have arrived during a certain monitoring period, and that whenever a new sample arrives at the input of the means, the means updates the calculated estimates on the basis of the new sample.
摘要:
In a method for controlling transmission power in a cellular communication system which utilizes a technique for canceling multiple access interference, and in which a receiver controls the transmission power of a transmitter on the basis of a received signal, power control is carried out on the received signal after the received signal has been subjected to interference cancellation.
摘要:
Interference in a cellular CDMA network due to mobile stations causing multiple use of one carrier frequency in neighboring cells is cancelled. A hard handover is implemented by defining the phase of a spread spectrum code in a signal transmitted from a base station to a mobile followed by measurement of signal strength in the mobile. Thereafter, the result is reported to the CDMA network, inferring whether the mobile interferes with the base station of the neighboring cells. If interference is present, the surrounding base stations are informed about the mobile station channel used, and this information is taken into account in the receivers of signals transmitted by other mobiles within the cell. The measurement results of the mobile are provided as initial values to the parameters required by the initialization of the interference cancellation routines performed in a neighboring base station. In another embodiment, it is decided whether the mobile station has to be monitored at the neighboring base stations by comparing the measurement results with a predetermined threshold value.
摘要:
This invention relates to power control arrangements of digital subscriber lines. The invention controls parallel subscriber lines simultaneously in an organized way, based on the measurements of crosstalk conditions of the sub-scriber lines. Different crosstalk conditions are measured. The organized way to control the transmission power levels ensures that the crosstalk does not increase to an unacceptable level in each of the subscriber lines.
摘要:
A receiving method and a receiver in a data transmission system in which CDMA multiple access is applied, the receiver having a decorrelating detector. In order that the receiver can function effectively both in the event of multiuser interference and on a multipath channel, the decorrelating detector of the receiver has separate equalizers for equalizing the effect of the multipath channel in the received signal, and filters matched with the codes contained in the received signal, and multipliers for multiplying the received signal by the inverse matrix of the cross-correlation matrix of the codes contained in the received signal.
摘要:
A method for estimating a channel in a receiver of a cellular radio system, and a receiver in a cellular radio system, the receiver comprising means (22) for subjecting the received signal to elimination of multiple access interference. To obtain good channel estimates, the receiver of the invention comprises means (23) for computing channel estimates from a signal that has undergone elimination of multiple access interference. (FIG. 2)
摘要:
The invention is related to a method and circuit arrangement for processing a received signal in a variable symbol rate system, such as a digital television system. In the method and arrangement according to the system, a received signal is sampled at a fixed sampling frequency (f.sub.f) that is higher than the symbol frequency of any one of the received signals. The resulting sample sequence is converted to another sample sequence the sampling frequency of which equals the symbol frequency (f.sub.i) of the received signal or its integer multiple. Then the samples are filtered (8) and signal value decisions are made (9) for the filtered samples. Conversion of the sampling frequency is advantageously performed using a so-called modified Farrow-type fractional delay filter (6) which is controlled using a control signal proportional to the delay of each sample. Using the method and arrangement according to the invention it is possible to process received signals the symbol frequencies of which are arbitrary within set limits.