Abstract: When a mobile station MS1 determines during communication through a first network (1), that a second network (7) is available that offers better operational parameters for the communication, the mobile station sends a handover announcement (S 5.3) to the first network to offer it an opportunity to improve the operational parameters for the communication through the first network. The first network (1) may in response offer updated operational parameters (S5.6) with a view to encouraging the communication to continue through the first network. A decision (S5.7) whether to make a handover to the second network can then be made by comparing the updated operational parameters for the first network with the operational parameters for the second network.

Abstract: When a mobile station MS1 determines during communication through a first network (1), that a second network (7) is available that offers better operational parameters for the communication, the mobile station sends a handover announcement (S 5.3) to the first network to offer it an opportunity to improve the operational parameters for the communication through the first network. The first network (1) may in response offer updated operational parameters (S5.6) with a view to encouraging the communication to continue through the first network. A decision (S5.7) whether to make a handover to the second network can then be made by comparing the updated operational parameters for the first network with the operational parameters for the second network.

Abstract: In a charging system for cellular communications, real-time prices for new connections are offered to the customer. The real-time prices take into account both prevailing and historic traffic patterns, together with the probability that the customer will move from their current cell into a neighboring cell. Cells of the network are monitored in clusters. If a customer is located in one particular cell, the price offered to that customer will take into account the probability of handover to a neighboring cell during the connection, and may also take into account the probability of incoming traffic from neighboring cells during the connection. To enable this predictive pricing, the system stores, and may also update, historic data.

Abstract: An optical detector for use in detecting digital optical signals has an optical fiber coupler which splits a received optical signal into two signal portions. The coupler has unequal length output fibers so that one signal portion impinges upon an associated photodetector delayed relative to the other. The photodetectors are connected in series nonopposed when the delay is equal to the bit period of the optical signal the output of the detector is the differential code (dicode) of the received signal which can be recovered by a high input impedance, i.e. integrating, amplifier. By forming the dicode in the optical domain in this manner large DC and AC dynamic ranges are obtained without linearity constraints on the optical transmission source that apply when the optical signal is transmitted as a dicode.