摘要:
Method and apparatus for supporting the Asynchronous Transfer Mode (ATM) connectionless service by means of Partial Connections (PCs) in an ATM system (18). These PCs are established between the source users (10, 11, 17) of said ATM system (18) and the destination switching nodes (14) to which the destination users (15) are linked. The use of PCs has no constraints on the size of the domain, because the information the source user (10, 11, 17) inserts in the Virtual Path Identifier/Virtual Channel Identifier (VPI/VCI) field of ATM cells to be transmitted to a destination user (15), is local to the source switching node (12) to which the source user (10, 11, 17) is connected. The information inserted in the VPI/VCI field identifies the PCs along which ATM cells are to be routed.
摘要:
The present invention proposes a method to filter electronic messages in a message processing system, this message processing system comprising a temporary memory for storing the received messages intended to users, a first database dedicated to a specific recipient, and a second database dedicated to a group of recipients, this method comprising the steps of:a) receiving an electronic message and storing it into the temporary memory, b) generating a plurality of proportional signatures of said message, each signature being generated from predefined length of the message content at random location, c) comparing with a first similarity threshold the generated signatures with the signatures present in the first database related to the message's recipient, and eliminating the generated signatures that are within the first similarity threshold of the first database's signatures, thus forming a set of suspicious signatures, d) comparing with a second predefined similarity threshold the suspicious signatures with activated signatures present in the second database, and flagging the message as spam if at least one of the suspicious signatures is within the second predefined similarity threshold of the second database's activated signatures, e) allowing a user to access the message, and moving said message from the temporary memory into a recipient's memory, f) if the message is accepted by the user, storing the generated signatures related to this message into the first database related to this recipient, g) if the message is declared spam by the user, using the suspicious signatures of said message in the second database for, either, if no similar signature exists, creating a non-activated signature into the second database with said signature or updating a previously stored signature that is within of a third similarity threshold of a suspicious signature by incrementing its first matching counter, and activating said previously stored signature if the matching counter is above a first counter threshold.
摘要:
The present invention concerns a receiver and a method for retrieving data from Ultra wideband radio transmission signals received by a receiver and transmitted in packets containing at least a preamble known to the receiver and a payload containing data unknown to the receiver. The payload data is formed of at least one burst containing at least one pulse. The method comprises the steps of receiving a signal corresponding to the preamble of a packet by a receiver; determining the energy of the received signal; determining weighting coefficients from the energy of the received signal; receiving a signal corresponding to the payload of a packet by a receiver; determining the energy of the received signal; calculating a threshold depending on the weighting coefficients; and applying a decision rule based on the sampled energy, weighted by said weighting coefficients and depending on said calculated threshold.
摘要:
In a system using the Asynchronous Transfer Mode (ATM) for data transfers, each cell is usually routed in response to VPI/VCI values identifying a previously established connection. A connectionless transfer mode is disclosed by which to each requesting user, a unique routing identifier (RI) is allocated. All RIs allocated in the whole network are kept in a table of a routing identifier management function (RIMF). When a source user wants to send a message to a destination user, it requests the destination RI from the RIMF and inserts the received RI into each transmitted cell in the VCI field. The RI may, include a switching node identifier (SI) and a port identifier (PI). In that case, each switching node has a permanent table of all SIs plus respective routing information, and a changing table of all currently allocated PIs of locally connected users plus the respective user port names.
摘要:
A generator of very short pulses where a cascade of inverters of arbitrary length characterized in that said inverters are adapted to produce pulses on their power supply line instead of their usual output.
摘要:
In a system using the Asynchronous Transfer Mode (ATM) for data transfers, each cell is usually routed in response to VPI/VCI values identifying a previously established connection. A connectionless transfer mode is disclosed by which to each requesting user, a unique routing identifier(RI) is allocated. All RIs allocated in the whole network are kept in a table of a routing-identifier management function (RIMF). When a source user wants to send a message to a destination user, it requests the destination RI from the RIMF and inserts the received RI into each transmitted call in the VCI field. The RI may, include a switching node identifier (SI) and a port identifier (PI). In that case, each switching node has a permanent table of all SIs plus respective routing information, and a changing table of all currently allocated PIs of locally connected users plus the respective user port names.
摘要:
Method for estimating and correcting a frequency offset between a local clock of a receiving transceiver and a remote clock of an emitting transceiver comprises receiving by said receiving transceiver, a signal emitted by the emitting transceiver, said signal lacking a continuous sinusoidal carrier and having at least one symbol, each symbol being emitted within a time frame having a first duration; sampling the signal by taking for each time frame a set of energy measurements of said signal; forming a matrix representative of said energy measurements; determining from said energy matrix, points of maximum of energy within each time frame; determining a line connecting a plurality of said points within each of said time frames; determining a slope of said line; calculating a frequency offset between the clocks of the emitting and receiving transceivers using the slope; and adjusting the receiving transceiver's clock frequency according to the frequency offset.
摘要:
A method to synchronize impulse radio signal in a receiver based on a cross-correlation between an input signal and a template pulse train is described. The method comprises the steps of receiving a radio signal, performing a correlation between the acquired radio signal and a template pulse train, splitting the correlation into at least two elementary correlations over intervals of predefined length and separated by a predetermined time to obtain elementary correlation output, performing an elementary threshold check on each elementary correlation output, summing the elementary threshold check outputs to form a sum result.
摘要:
This invention defines a routing method which allows a determination of best paths from link weights in situations where these weights are not additive, but the characteristic of a concatenated path is determined mainly by single "bottleneck" links. To be compatible, the metric must be chosen from a specific set of metrics, called bottleneck metrics in this description. The new widest-path method has some characteristics in common with the known Dijkstra method for additive weights. Implementations in communication networks are disclosed which lead to new nodes, new networks and new network protocols.
摘要:
Method for estimating and correcting a frequency offset between a local clock of a receiving transceiver and a remote clock of an emitting transceiver comprises receiving by said receiving transceiver, a signal emitted by the emitting transceiver, said signal lacking a continuous sinusoidal carrier and having at least one symbol, each symbol being emitted within a time frame having a first duration; sampling the signal by taking for each time frame a set of energy measurements of said signal; forming a matrix representative of said energy measurements; determining from said energy matrix, points of maximum of energy within each time frame; determining a line connecting a plurality of said points within each of said time frames; determining a slope of said line; calculating a frequency offset between the clocks of the emitting and receiving transceivers using the slope; and adjusting the receiving transceiver's clock frequency according to the frequency offset.