Telephone line monitoring apparatus and method

• US 5,347,572 A
• Filed: 09/05/1991
• Issued: 09/13/1994
• Est. Priority Date: 09/06/1990
• Status: Expired due to Fees

• Current Assignee: Teletron, Inc.
• Original Assignee: Teletron, Inc.
• Inventors: Avni, Shlomo
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): Woo, Stella L.
• Application Number:
  US07/755,128
• Time in Patent Office: 1,104 Days
• Field of Search: 379/100, 379/85, 379/67, 379/68, 379/88, 379/412, 379/35, 379/34, 358/444, 358/400, 358/401, 358/442, 358/468
• US Class Current: 379/93.17
• CPC Class Codes: G01R 19/003 Measuring mean values of current or voltage during a given time interval
• CPC Class Codes: G01R 19/16528 using digital techniques or performing arithmetic operations using digital techniques to measure a voltage or a current, see G01R19/25
• CPC Class Codes: G01R 19/25 using digital measurement techniques
• CPC Class Codes: G01R 27/16 Measuring impedance of element or network through which a current is passing from another source, e.g. cable, power line
• CPC Class Codes: H04M 1/82 Line monitoring circuits for call progress or status discrimination for detecting caller identity H04M1/573
• CPC Class Codes: H04N 1/00 Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
• CPC Class Codes: H04N 1/00002 Diagnosis, testing or measuring; Detecting, analysing or monitoring not otherwise provided for error detection, error correction or monitoring in digital computers or digital computer components G06F11/00
• CPC Class Codes: H04N 1/0001 Transmission systems or arrangements
• CPC Class Codes: H04N 1/00039 Analysis, i.e. separating and studying components of a greater whole
• CPC Class Codes: H04N 1/00042 Monitoring, i.e. observation H04N1/00029 - H04N1/00039 take precedence
• CPC Class Codes: H04N 1/0009 Storage
• CPC Class Codes: H04Q 1/32 using trains of dc pulses H04Q1/39 takes precedence
• CPC Class Codes: Y10S 379/908 Multimedia

Abstract

A fax monitoring apparatus comprises one or more line interface circuits to simultaneously detect and analyze audio signals produced on any given telephone line by two connected fax machines, analyzing circuitry to analyze and interpret the audio signals to form a compressed fax image, expansion circuitry to expand the compressed fax image into a bit-mapped image, memory to store the compressed fax image and/or the bit-mapped image, and display to display the bit-mapped image of the original fax transmission.

Claims

1. Fax monitoring apparatus, comprising:

line interface means connected in parallel to a telephone line for simultaneously detecting and analyzing audio signals produced on the telephone line by two fax machines communicating through the telephone line;

analysis means for analyzing and interpreting the audio signals to form a compressed fax image;

expansion means for expanding the compressed fax image into a bit-mapped image;

storage means for storing the compressed fax image and/or the bit-mapped image; and

display means for displaying the bit-mapped image of the original fax transmission.

2. Apparatus according to claim 1, wherein the storage means comprises a temporary memory or buffer, and one or more hard disks.

3. Apparatus according to claim 2, wherein the storage means further comprises one or more of the following:

a digital cartridge recorder, a floppy diskette drive and an optical disk drive.

4. Apparatus according to any one of claims 1 to 3, wherein the analysis means comprises a modem and wherein a separate modem is provided for each monitored telephone line.

5. Apparatus according to claim 4, further comprising an analog-to-digital transducer connected in series to each modem, to transform into digital storable information audio signals transmitted through the telephone line.

6. A method of monitoring fax communication in a system that includes:

line interface means connected to a telephone line to be monitored;

activating means for detecting line activity comprising one of start/stop activity, ringing and dialing pulse and DTMF signalling; and

interpreting means activated by the activating means, the method comprising the steps of;

connecting line interface means in parallel to a telephone line for simultaneously detecting and analyzing audio signals produced on the telephone line by two fax machines communicating through the corresponding telephone lines;

interpreting fax transmission by means of the interpreting means when line activity is detected;

assembling the interpreted fax transmission into compressed fax images;

storing the compressed fax images in memory means;

retrieving the stored compressed fax images and expanding them to bit-mapped images on display means; and

displaying the bit-mapped images on the display means.

7. A method according to claim 6, wherein the display means comprise a screen and/or a printer.