Single matrix telephone exchange system - has multi-connection capability on single crosspoint row structure to reduce matrix size

摘要

The single switching matrix is for small PABX etc. telephone installations providing internal connection between extensions and connection through to exchange lines. The size of the matrix has been reduced and has the extensions connected to the outlets. The tie lines and exchange lines are connected to the inlets. Extension-to-extension calls are routed over crosspoints in the same inlet row as connections between extension and external line (ExV), minimal additional, typically one, extra inlet row is provided for internal connections to prevent switch blocking. The total crosspoint count is calculated using the number of external connections and the sum of the difference between external and extension counts. Operationally, any extension (Tln1 ..Tln6) can be connected to another using an inlet row (Ltg1...Ltg3) which would also be used to connect an extension to an external line (ExV,Ltg1..Ltg3).