Abstract: A composition comprises, based on the total weight of the composition, from 5 to 95 weight percent of a polycarbonate and from 5 to 95 weight percent of a poly(ester-ether) copolymer. The poly(ester-ether) copolymer comprises units derived from terephthalic or a chemical equivalent thereof, units derived from butane diol or a chemical equivalent thereof, and 23 to 70 weight percent of units derived from poly(oxytetramethylene) glycol or a chemical equivalent thereof, based on the weight of the copolymer. The composition also comprises from 0.001 to 0.5 weight percent of a quencher. The composition exhibits a Shore D in the range of 45 to 75; and a low temperature notched Izod ductility of at least 80% at ?40° C., as measured by ASTM D256.

Abstract: A thermoplastic resin composition is disclosed which includes: structural units derived at least one substituted or unsubstituted polycarbonate, and a polyester comprising structural units derived from at least greater than 40 mole percent of xylene glycol, such that the composition is miscible. Also disclosed is a process of making said thermoplastic compositions and articles derived from said composition. The composition disclosed possess good optical properties, thermal properties and stability.

Abstract: In a mobile communications system 10, a message is sent to a mobile terminal 16 which transmits an acknowledgement signal if the message is received. If the system 10 does not detect an acknowledgement signal, it transmits a high margin notification signal to the mobile terminal 16 to notify the terminal that an attempt was made to send the message. When the mobile terminal 16 has received a notification signal and subsequently comes within range of lower margin signals from the system, it sends a registration signal to the system. The system may then retransmit the message to the mobile terminal 16.

Abstract: In a mobile communications system 10, a message is sent to a mobile terminal 16 which transmits an acknowledgement signal if the message is received. If the system 10 does not detect an acknowledgement signal, it transmits a high margin notification signal to the mobile terminal 16 to notify the terminal that an attempt was made to send the message. When the mobile terminal 16 has received a notification signal and subsequently comes within range of lower margin signals from the system, it sends a registration signal to the system. The system may then retransmit the message to the mobile terminal 16.

Abstract: In a mobile communications system 10, a message is sent to a mobile terminal 16 which transmits an acknowledgement signal if the message is received. If the system 10 does not detect an acknowledgement signal, it transmits a high margin notification signal to the mobile terminal 16 to notify the terminal that an attempt was made to send the message. When the mobile terminal 16 has received a notification signal and subsequently comes within range of lower margin signals from the system, it sends a registration signal to the system. The system may then retransmit the message to the mobile terminal 16.

Abstract: In a preferred satellite (3) communications environment, spread spectrum communications, under extremes of digital message readability, is established for a digital message 23 by division into smaller elements W(0)-W(C−1) which are transmitted in turn, each multiplied for logical inversion or non-inversion, by the individual, sequential digits of a preferred binary polynomial 35, being either a PN polynomial, an m-polynomial, or simply displaying alternate logical ones and zeroes. The preferred polynomial may be used convey an alternative polynomial for better reception of a subsequent digital message.

Abstract: In a satellite position fixing system, where an earth station 38 communicates with a satellite 10 which, in turn, communicates with selectable ones out of a plurality of user terminals 44 whose position, on the surface of the earth 14, is measured, the accuracy of measurement of the position of the satellite 10 is improved by using all of the user terminals 44 as further triangulation points, the improved position being incorporated in further user terminal 44 position determinations, and so on to create a cumulative improvement. Weighting is applied so that user terminals 44 with large errors in triangulation are given small significance and those with small errors are given great significance.