Abstract: A base-band and broad-band coexisting communication system comprises a transmission path, a plurality of first data terminal units outputting data to be transmitted in the form of pulse signals (base band signals), a plurality of second data terminal units for outputting data to be transmitted in the form of modulated signals (broad band signals) each having a center frequency within a predetermined frequency range, and a plurality of low-pass filters, each connected to each of the first data transmission units, for cutting off high frequency components of the base band signal outputted by the first data terminal device at a predetermined cut-off frequency which does not overlap with the broad band signals.

Abstract: A protocol high-speed processing method to be used in a first communication control equipment for communications with a second communication equipment connected through a transmission line in accordance with a predetermined communication protocol. The communication control equipment predicts the type of communication frame to be received next from the communication line, in accordance with type of communication frame previously transmitted to or received from said transmission line, and prepares information necessary for a process of receiving said predicted communication frame and information of a part of the communication frame to be transmitted subsequent to the receiving process, to await the reception of a next communication frame. As a result, the receiving process time and the response process time can be reduced when the actually received communication frame is consistent with the predicted one.

Abstract: This invention is directed to a microporous film comprising a 40 to 90 volume percent polyolefin having a number average molecular weight of 15,000 or more and a weight average molecular weight of less than 300,000 and a 10 to 60 volume percent inorganic filler and having a void space rate or porosity of 30 to 75 volume percent based on the volume of the film. The microporous film of such specific composition and structure has a desired wettability and a much reduced electrical resistance. Said resistance being as low as 0.0006 .OMEGA.dm.sup.2 /sheet. Said film has sufficient flexibility and mechanical strength to make it useful in wide variety of applications, especially as separators in batteries or electrolytical apparatuses etc.