摘要:
The present invention provides a method, base station and user equipment for transmitting data in a mobile communications system, wherein said data is transmitted on at least one channel between at least one base station with multiple antennas and at least one user equipment. The base station applies precoding to the data based on a set of predefined codebooks. A first tracking mode with a first codebook from said set of predefined codebooks is used for said precoding, and at least a second tracking mode with at least a second codebook from said set of predefined codebooks is used for said precoding. The base station switches between said first tracking mode and said second tracking mode depending on at least one condition of said channel.
摘要:
It is described a method for transmitting channel quality information between a second network element and a first network element. The method includes (a) dividing a range of possible radio channel qualities between the two network elements into a fixed number of quality classes, (b) measuring the quality of a radio channel between the two network elements, (c) selecting one quality class out of the fixed number of quality classes based on the measured quality of the radio channel, (d) transmitting from the second network element to the first network element a first channel quality information being indicative for the selected quality class, and (e) transmitting from the second network element to the first network element a second channel quality information being indicative for the measured quality within the limits of the selected quality class. It is further described the first and the second network element, which in conjugation with each other are adapted to carry out the described method.
摘要:
It is described a method for transmitting channel quality information between a second network element and a first network element. The method includes (a) dividing a range of possible radio channel qualities between the two network elements into a fixed number of quality classes, (b) measuring the quality of a radio channel between the two network elements, (c) selecting one quality class out of the fixed number of quality classes based on the measured quality of the radio channel, (d) transmitting from the second network element to the first network element a first channel quality information being indicative for the selected quality class, and (e) transmitting from the second network element to the first network element a second channel quality information being indicative for the measured quality within the limits of the selected quality class. It is further described the first and the second network element, which in conjugation with each other are adapted to carry out the described method.
摘要:
The invention relates to a method and/or an OFDM device for SC-FDMA data transmission in which a sequence of input data (x(i), i = 1, 2, 3,..., N) is transformed by means of a discrete transformation (DFT) as transformed data signals (yi, i = 1, 2, 3,..., N) of coded and modulated data signals on first frequency channels (f1, f2, f3,..., fN) into a first frequency space over a first number of frequencies (N), the transformed data signals (yi) are mapped on second frequency channels (f1*, f2*, f3*,..., fN *,...., fNc*) in a second frequency space with a larger second number of frequencies (Nc), the transformed data signals on the second frequency channels are inverse-transformed using an inverse transformation (IFFT), and data (zi) inversely transformed in such a way are provided for transmission. On this basis, the transformed data signals (yi) are mapped into a frequency range (fi+1*,..., fi+N*) of the second frequency channels in such a way that a constant component (y1, f1) of the transformed data signals (yi) is mapped centrally within the frequency range (fi+1*,..., fi+N*).
摘要:
A method for operating a radio communication system involves the use of OFDM and involves a first sending station modulating a first OFDM symbol onto a first carrier frequency and sending the first OFDM symbol to a first receiving station via a first transmission channel using an air interface. In line with the invention, the first sending station changes the first carrier frequency during a time used for sending the first OFDM symbol, the change in the first carrier frequency being made independently of a change in transmission characteristics of the first transmission channel over time. A fast frequency hopping system (FFH-OFDM) is disclosed.
摘要:
It is described a method of operating a base station and a base station which uses a communication channel depending on channel state related information and time information e.g. a prediction time. In this way, problems due to outdating of the channel state related information may be overcome and a feedback overhead may be reduced. According to other embodiments, other parameters like a used prediction method, a prediction horizon, etc. are used to provide a better scenario adaption. Other embodiments relate to combined long term prediction and short term prediction and respective timing settings. Other embodiments relate to a method of operating a user equipment and a user equipment which is adapted for communicating the required time information between the base station and the user equipment.
摘要:
A method for transmitting a signal is described, wherein the method has transforming a signal into a frequency domain to obtain a spectrum, forming a filtered spectrum according to a filter spectrum and occupying a set of subcarriers of a frequency domain representation of an Orthogonal Frequency Division Multiplex (OFDM) signal with the filtered spectrum. A temporary signal is obtained by transforming the frequency domain representation of the OFDM signal into a time domain. The temporary signal is subjected to a phase modulation.
摘要:
It is provided a signal processing system, comprising at least a first, a second and a third digital-to-analog converter (DAC); a processing unit configured for splitting a sampled signal into a first and a second signal corresponding to different frequency portions of the sampled signal, transmitting the first signal to the first DAC, splitting the second signal into a first and a second subsignal and transmitting the first subsignal to the second DAC and the second subsignal to the third DAC, the first subsignal corresponding to the real part of the second signal and the second subsignal corresponding to the imaginary part of the second signal; an IQ mixer configured for mixing an analog output signal of the second DAC and an analog output signal of the third DAC and a combiner for combining an analog output signal of the first DAC and an output signal of the IQ mixer.