摘要:
For synchronizing one or more receivers (E) to a transmitter (S) within a transmission system, the transmitter (S) inserts a special synchronization train into the data stream. The synchronization train is formed of at least two different symbol sequences (A, B), which are transmitted periodically in alternation.
摘要:
In a method of digital data transmission in a wireless communication network in which a controlling communication takes place within a fixed bandwidth of a channel from a master station to all subscribers (downlink) with the help of a fixed signal frame, and the beginning of the fixed signal frame is marked by a special frame synchronization signal detectable by the subscribers, an occupancy of at least one subband by transmission signals and a non-occupancy of at least one complementary subband by transmission signals is used as a frame synchronization signal.
摘要:
In a device for data transmission having a central station and a plurality of subscribers, in addition to useful signal data phases, signaling data phases are provided for the downlink and uplink in a transmission frame (3). The signaling data phases for the downlink are divided into signaling data phases related to the central station and related to the protocol. The positions of these two signaling data phases are identified directly or indirectly by identifiers.
摘要:
A method for handing over a link between a mobile station and a network from a first base station to a second base station of the network. In the case of an existing link, link data for the link are stored in the base station in question and resources of the base station are held in reserve for the link. When a link is handed over, the link data initially remain stored in the first base station and the resources of the first base station initially remain held in reserve. At a later timepoint the link data are deleted and the resources are freed up. Furthermore, a method is used in which in the case of a handover the mobile station sends the network a query as to whether the network can support the handover by transferring the link data from the first mobile station to the second mobile station. If the mobile station is informed that the network cannot support the handover the mobile station makes the link data available to the second base station.
摘要:
In a method of power saving operation of communication terminals in a communication system, at least two operating modes are defined: active and sleep plus optionally standby. Announcements sent out from a master station over an announcement channel are monitored within fixed time windows and thereafter the operating modes of the terminals are controlled. Synchronization information/frame symbols from the master station are also analyzed in the sleep phases and in the standby phases.
摘要:
Transmission resource allocation by a central station (ZE) for control of data flow of terminals (T1, T2, . . . ) of a centrally controlled communication system is performed in the terminals (T1, T2, . . . ). A concerned terminal (T1, T2, . . . ) independently decides whether it might only need reduced transmission resource capacity. The decision regarding this reduction in needed transmission capacity is transmitted to the central station, so that it can distribute the unneeded transmission capacity to the remaining terminals.
摘要:
A method of allocating transmission resources to respective terminals in a centrally controlled communication system in which the transmission resource allocation to the terminal is performed by a central unit includes allocating the transmission resources for at least one frame-oriented connection of a deterministic kind, particularly such that operates with a substantially constant data rate, independently of any previously issued resource requests for non-deterministic connections; providing a special designation for such a deterministic connection to distinguish the same from other connections; and correcting non-synchronous timing between the central unit and the affected terminals particularly for such a deterministic connection.
摘要:
In a method for repeat transmission of messages in a centrally controlled communication network including a plurality of terminals and a central station messages assigned sequence numbers are broadcast or multicast from the central station for reception by terminals of a participating group. As soon as a terminal detects loss of a transmitted message or an error in the transmitted message, it transmits a repeat request for repeat transmission of that message, which includes the sequence number of the lost or erroneous message, over another communication link, especially a point-to-point communication link. The central station repeats the message transmission of the lost or erroneous message but only until a predetermined maximum number of repetitions occurs within a predetermined time interval or until a positive acknowledgement of receipt of the previously lost or erroneous message is received.
摘要:
A process, a control center, and a terminal device are proposed for transmitting messages to terminal devices in a, in particular, wireless, telecommunications system with a control center and with terminal devices. The transmission protocol is frame structured in the time domain. In the transmission protocol, the terminal devices ignore messages from the control center during a single frame, or several consecutive frames. The following steps are carried out in order to transmit a message to one terminal device or to a plurality of terminal devices: First, a number of terminal device groups which includes the majority of the terminal devices are formed by the control center. Each terminal device belongs to exactly one terminal device group and all terminal devices of a terminal device group are ready to receive messages during the same frame. Second, the message that is to be sent is transmitted to each of at least one terminal device group during one possible frame.
摘要:
A broadband data transmission method in a wireless cellular network, the data to be transmitted being transmitted as packet-oriented data, preferably by means of ATM cells. An additional narrow-band signaling channel transmits signaling information necessary for managing the cellular, wireless network.