METHOD OF AND ARRANGEMENT FOR ESTABLISHING A CONFERENCE CONNECTION IN A TDM COMMUNICATION SYSTEM

摘要

To establish a conference connection between three participants in a TDM telephony system, use is made of the time-division switching stage which in many cases is already of a duplicated construction. The information signals (a, b, c) from the participants are written into corresponding addresses (AA, BB, CC) of two information memories while these addresses, after having been cyclically permuted, are written into the address memory associated with each of the information memories. When now the locations in the information memories are read in the sequence indicated by the address memories and summed thereafter, then each participant in the conference is supplied with a conference signal which is equal to the sum of the information signals of the two other participants in the conference connection.