摘要:
A multicarrier receiver (RX') comprises the cascade connection of a sliding Fourier transformer (SLIDING FFT) which subsequently Fourier transforms parts of an incoming cyclically extended multicarrier symbol (MS), and a per-carrier frequency domain equaliser (PC-FEQ) including for each carrier a tapped delay line (TD1, TD2, ..., TDN/2) for equalising the Fourier transformed parts of the incoming multicarrier symbol (MS). The per-carrier frequency domain equaliser (PC-FEQ) allows to optimise the system capacity individually per carrier, and in a preferred embodiment of the invention includes tapped delay lines (TD1, TD2, ..., TDN/2) with adaptive complex taps, with an adaptive length and with an individual delay that may differ for different carriers.
摘要:
Modems (1) for coupling network-units (40) to devices (50) and comprising receivers (21) for receiving first data from the network-units (40) and transmitters (22) for transmitting second data to the network-units (40), which first data is destined for the devices (50) and which second data originates from the devices (50), are provided with detectors (31) for detecting parameters (p 1 ) of the first data and adjustors (32) for, in response to detection results, adjusting parameters (p 2 ) of the second data, to reduce the chance on network congestion networks (4). Calculators (33) calculate the parameters (p 2 ) of the second data as a function of the parameter (p 1 ) of the first data. The parameter (p 2 ) of the second data is made substantially equal to the parameter (p 1 ) of the first data between a minimum value (b min ) and a maximum value (b max ). The parameters (p 1 ,p 2 ) comprise a bitrate. The network-unit (40) forms part of an access network (4) and the device (50) forms part of a subscriber network (5).
摘要:
The invention relates to a reception arrangement for receiving multicarrier symbols, each multicarrier symbol (S 1 , S 2 , S 3 ) comprising a plurality of single carrier symbols, each symbol modulating a respective carrier frequency (f 1 , f 2 , f 3 ). The single carrier symbols are transmitted simultaneously. The arrangement comprises means for detecting phase error of each single carrier and means for correcting the phase of a sampling clock (52) in view of the estimated error. The means for estimating phase error comprise means (58 1 ... 58 N , 24, 40) for determining a parameter êi for a carrier fi according to the following formula: wherein rik is the detected signal for the single carrier at a time t, aik is the corresponding symbol at the same time t, aik-1 and rik-1 correspond, respectively, to aik and rik at time t-NT, NT being the duration of transmission of a multicarrier symbol, and E[ ] means an average value on several successive symbols.
摘要:
In the course of a reflectometry-based qualification procedure of a local loop, which connects customer premises to a central office of a telecommunication network, and in the event of being unable to identify the loop termination associated with the customer premises, a second reflectometry measurement of the local loop is carried out with a different impedance load at the customer premises. Next, the two reflectograms are compared with each other in the time domain in order to delineate among all the reflections those at the customer premises and to determine therefrom the position of the customer premises in the local loop.
摘要:
The present invention is related to an apparatus comprising a tunable active circuit, said circuit synthesising a self-induction. The invention is characterised in that said active circuit comprises only one balanced/balanced Operational Amplifier.
摘要:
The invention relates to a reception arrangement for receiving multicarrier symbols, each multicarrier symbol (S 1 , S 2 , S 3 ) comprising a plurality of single carrier symbols, each symbol modulating a respective carrier frequency (f 1 , f 2 , f 3 ). The single carrier symbols are transmitted simultaneously. The arrangement comprises means for detecting phase error of each single carrier and means for correcting the phase of a sampling clock (52) in view of the estimated error. The means for estimating phase error comprise means (58 1 ... 58 N , 24, 40) for determining a parameter êi for a carrier fi according to the following formula: wherein r i k is the detected signal for the single carrier at a time t, a i k is the corresponding symbol at the same time t, a i k-1 and r i k-1 correspond, respectively, to a i k and r i k at time t-NT, NT being the duration of transmission of a multicarrier symbol, and E[ ] means an average value on several successive symbols.
摘要:
The invention relates to a method for transferring information, especially control commands or operational data, between a master device and a slave device, especially the central station (CS) of a public utility company (PUV) and an access device (AD1, AD2, AD3; AD) of a consumer (C1, C2, C3), wherein transferring information is performed with the aid of a publicly accessible communications network (PCN), that registration of the slave device (AD1, AD2, AD3; AD) with a central instance (C1) precede the transfer of information, and that the access of the master to the slave or of the slave to the master is performed with the aid of the central instance (C1) or based on information got from the central instance (C1). The invention further relates to a system, a master device (CS), a slave device (AD1, AD2, AD3; AD), and a central instance (C1).