Abstract: An estimate is made of the power of a speech portion of a speech signal that includes speech portions separated by non-speech portions, the power for the speech portion being estimated based on a power envelope that spans the speech portion. The gain of an automatic gain control is not adjusted during the speech portions.

Abstract: At least a fax message is sent via a telephone system to a telephone receiving station. From that receiving station, the fax message is routed through a multinode computer network to a prespecified network location. A telephone call by which the fax message is transmitted is initiated by dialing a telephone number such as a DID number. Part of the telephone address signal is received at the receiving station and used to establish a connection to a network location such that a fax message may be sent to or from the network location. The network location may be a mailbox associated with an intended recipient. The DID receiver may initiate a call to a second receiver using a ringing signal with routing information communicated through a separate data link.

Abstract: A method for causing information including at least FAX messages sent via a telephone system to be subjected to prespecified actions at a FAX receiving station. A telephone call is initiated via the telephone system to the FAX receiving station by dialing a telephone number sufficient to route the telephone call to the FAX receiving station, the telephone number also being sufficient to determine the prespecified actions to which the FAX message is to be subjected at the receiving end. The telephone number is carried through the telephone system in the form of a telephone address signal as part of the call initiation process. The telephone call being initiated is directed to the FAX receiving station, based on the telephone address signal. The telephone call is answered at the FAX receiving station, and the telephone address signal is received at the FAX receiving station.

Abstract: Delivery of binary encoded character data and facsimile encoded data to a specified recipient is controlled rapidly, simply, and with versatility, by, e.g., DTMF commands sent by a user.

Abstract: An envelope detector comprising an absolute value detection portion and a filter portion implemented in switched capacitor technology with common circuit elements is provided. The absolute value of an input signal is obtained and an amplitude envelope is filtered therefrom. The absolute value detection portions and the filter portions share the same integrating operational amplifier to perform the envelope detection.