摘要:
A mobile radio communication system including at least one exchange, a network including a plurality of base stations, and a mobile station communicating simultaneously with the plurality of base stations, in which the transmission delay between the local station and the base stations varies in response to a plurality of service types that can be provided to the mobile station. It is the objective of the technique that communication with an appropriate transmission delay in response to the service type is to be enabled, and synchronization is to be recovered even when pull out occurs. Therefore, a storage member (processor (32) in local station) for storing the transmission delay for each service type in response to the plurality of service types that can be provided to the mobile station is provided. In addition, a setting member (diversity hand-over trunk (34) for setting the communication timing at each of the base stations on the basis of the transmission delay corresponding to the service type applied to the mobile station is provided.
摘要:
The invention reduces an overhead operation required for re-establishment of a physical signal link. A physical signal link (layer 1 link) is switched over keeping a layer 2 link in the OSI reference model. A database 11 stores information indicating physical signal links and information indicating the maximum length of a layer 2 frame determined according to the ability of physical signal links. When a physical signal link is to be switched over, a target physical signal link is selected and a physical signal link used by the link is switched to the target physical link without releasing the single layer 2 link. The maximum length corresponding to the target physical signal link is obtained from the database 11, and layer 2 frames having the maximum length are transmitted. Switching over a physical signal link is performed in the following manner. When a physical signal link switching-over request is given, establishment of a target physical signal link is required without releasing a layer 2 link, and a multi-reception of control signals using both of the target physical signal link and an original physical signal link is started. After confirming establishment of the target physical signal link, a physical signal link used for transmitting a control signal is switched to the target physical signal link and release of the original physical signal link is required. After confirming release of the original physical signal link, a physical signal link for receiving a control signal is switched to the target physical signal link.
摘要:
A multiplex system for multiplexing packets into ATM cells to be transmitted, which can implement effective use of channels corresponding to irregular traffic qualities in services with various types of quality conditions in an actual environment. In response to a connection establishment request (S402), current required bandwidths B1, ..., Bm are changed to B'1, ..., B'm by adding the new connection, which causes bandwidths X1, ..., Xm which are assigned to the channels to be changed. When the desired bandwidth including the requested connection is less than an available bandwidth of the corresponding channel, an assigned bandwidth change processing (S406) is activated to assign new bandwidths in accordance with desired bandwidths. The bandwidth assignment change is carried out by changing ratios of extraction rates of packets from the buffers in the multiplex system.
摘要:
A concrete circuit configuration is proposed of a multiplex transmitter for loading a standard ATM cell with multiplexed micro-frames which are each shorter than the standard ATM cell. The input micro-frames are delivered to a distributor (504) in the input order through an interface (503). The distributor (504) distributes the input micro-frames using distributing information input. The distributing information accords with the service condition of each connection or micro-frame. An extracting circuit (506) selects buffers in accordance with predetermined buffer selection logic. A cell cancellation monitor circuit (508) relinquishes micro-frames exceeding cell tolerable time periods T2-1 - T2-m. A multiplexing processor (507) transfers the cell or a idle cell to a sender (511) in accordance with the cell transfer timing of the sender (511).
摘要:
A mobile radio communication system including at least one exchange, a network including a plurality of base stations, and a mobile station communicating simultaneously with the plurality of base stations, in which the transmission delay between the local station and the base stations varies in response to a plurality of service types that can be provided to the mobile station. It is the objective of the technique that communication with an appropriate transmission delay in response to the service type is to be enabled, and synchronization is to be recovered even when pull out occurs. Therefore, a storage member (processor (32) in local station) for storing the transmission delay for each service type in response to the plurality of service types that can be provided to the mobile station is provided. In addition, a setting member (diversity hand-over trunk (34) for setting the communication timing at each of the base stations on the basis of the transmission delay corresponding to the service type applied to the mobile station is provided.
摘要:
A base station including a transmitting and receiving amplifier for amplifying CDMA signals exchanged with a mobile station; a radio stage connected to the transmitting and receiving amplifier for carrying out D/A conversion of a transmitted signal that undergoes baseband spreading, followed by quadrature modulation, and for carrying out quasi-coherent detection of a received signal, followed by A/D conversion; a baseband signal processor connected with the radio stage for carrying out baseband signal processing of the transmitted signal and the received signal; a transmission interface connected with the baseband signal processor for implementing interface with external channels; and a base station controller for carrying out control such as management of radio channels and establishment and release of the radio channels. The base station communicates with the external channels using ATM cells, and with the mobile stations using the CDMA signals by mapping a plurality of logical channels into a plurality of physical channels. The CDMA signals are spreading using two types of spreading code sequences, that is, a short code and a long code.