摘要:
Polyphenylene oxides, self-condensation products of phenols, are prepared with a high yield through oxidative coupling by employing a catalyst system with higher activity, which comprises a copper compound, iodine or an iodine-containing compound and a primary amine.
摘要:
Polyphenylene oxides, self-condensation products of phenols, are produced through oxidative coupling by employing a novel catalyst system which comprises a copper compound, an iodine compound and tertiary diamine which is capable of forming a stable chelate ring with the copper compound.According to this invention, copper compounds, which hitherto have been considered to be unsuitable for using with tertiary amines, act with excellent performance as a component of the catalyst.
摘要:
In a communication system 10, a management device 100, which is under the control of the MVNO, collects radio quality information from a UE 500 by using a communication channel established between the management device 100 and the UE 500, selects an optimum cell by using the collected radio quality information, and notifies the UE 500 of the selected optimum cell. The UE 500 then connects or hands over to the optimum cell notified by the management device 100.
摘要:
A mobile communication system includes a data multiplexer which divides by time a radio frame of a communication channel in a radio layer and multiplexes one of a plurality of pieces of multicast data and a plurality of pieces of broadcast data into the divided radio frames; and a data multiplex demultiplexer which demultiplexes, when receiving one of the plurality of pieces of multicast data and the plurality of pieces of broadcast data multiplexed by the data multiplexer, the multiplexing of the received data.
摘要:
In a mobile communication system, which has a plurality of radio network controllers and a number of radio base stations connected to each of the radio network controllers, for sending and receiving user data between a host network and mobile stations via the radio network controllers and radio base stations, a plurality of transmission paths that pass through one or more radio network controllers are set up between a base station, which sends and receives radio signals to and from a mobile station, and the host network. When data is being sent and received using one transmission path from the host network to a base station through a radio network controller, traffic conditions on this transmission path are monitored. When traffic has increased, the user data is dispersed by being passed through a plurality of transmission paths.
摘要:
A controller which is assigned with the wireless resources for a plurality of wireless zones and a plurality of wireless base stations communicably connected to the controller, wherein the controller is operable to assign a part of the assigned wireless resources to the wireless zone formed by any of the wireless base stations. According to this, it is possible to introduce and run a great number of wireless base stations at a low cost without increasing or modifying the number of the superordinate devices such as RNC.
摘要:
A base station, to which a cell belongs and which communicates with a relay node to which a relay node cell belongs, including a control unit configured, at a time of handing over the relay node from another cell belonging to a first base station to the cell belonging to the base station, to request the relay node to measure wireless quality of neighbour cells of the cell belonging to the base station and report a measurement result of the wireless quality, and to update by adding or deleting, if the measurement result of the wireless quality of a first neighbour cell among the neighbour cells is higher or lower than a predetermined threshold for the cell existing at the handover destination of the relay node, the relay node cell to or from a first neighbour cell list of the first neighbour cell, respectively.
摘要:
A frequency band adjusting method, in a first communication system and a second communication system sharing usable frequency band with each other, for adjusting the frequency band used by a first communication apparatus in the first communication system, comprising: determining whether or not increase in the frequency band used by the first communication apparatus is necessary based on the frequency band used by the first communication apparatus and the number of access to the first communication apparatus; determining whether or not increase in the frequency band used by the first communication apparatus is to be approved, according as there is or there is not unused frequency band not used by a second communication apparatus in the second communication system having coverage overlapping with the first communication apparatus; and, if increase is approved, increasing the frequency band used by the first communication apparatus.
摘要:
A communications system having an ATM transmission line and an IP transmission line is disclosed that includes a base station capable of communicating with a mobile terminal through a radio link; and a radio network controller capable of communicating with the base station through the ATM or IP transmission line. The radio network controller includes a division part dividing transmission data into signals of a predetermined data size; a transmission part transmitting the divided signals to the base station at predetermined time intervals; a retransmission part retransmitting the signals transmitted to the base station when a response signal from the mobile terminal is not received within a predetermined period; a measuring part measuring a signal response period in a communications channel between the radio network controller and the mobile terminal through the base station; and a determination part determining the predetermined data size based on the measured response period.
摘要:
In a mobile communication system, which has a plurality of radio network controllers and a number of radio base stations connected to each of the radio network controllers, for sending and receiving user data between a host network and mobile stations via the radio network controllers and radio base stations, a plurality of transmission paths that pass through one or more radio network controllers are set up between a base station, which sends and receives radio signals to and from a mobile station, and the host network. When data is being sent and received using one transmission path from the host network to a base station through a radio network controller, traffic conditions on this transmission path are monitored. When traffic has increased, the user data is dispersed by being passed through a plurality of transmission paths.