Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GB848408184Aexternal-prioritypatent/GB8408184D0/en
Priority claimed from GB848414208Aexternal-prioritypatent/GB8414208D0/en
Application filed by British TelecommfiledCriticalBritish Telecomm
Priority claimed from EP85302211Aexternal-prioritypatent/EP0157610B1/en
Application grantedgrantedCritical
Publication of ATE46401T1publicationCriticalpatent/ATE46401T1/en