Interface for connecting computers to radio telephone networks
Patent 5353334 Issued on October 4, 1994. Estimated Expiration Date: January 6, 2014. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
A system for connecting a computer to both cellular and landline telephone systems is disclosed. A cellular modem has a single RJ-11 jack for interfacing either to a landline jack or to a signal processing cable connected to a cellular transceiver. The analog data transmission signals of the modem, which are compatible with landline "tip" and "ring" lines, are provided on the third and fourth pins of the RJ-11 connector. When the modem is to be used as a landline modem, the RJ-11 connector is connected directly to a standard landline telephone jack using an ordinary modular telephone wire. When used with a cellular transceiver, the modem generates transceiver operation commands according to a predefined generic command language which is not specific to a particular transceiver. The generic commands are transmitted in serial digital form on the fifth terminal of the RJ-11 connector. The signal processing cable acknowledges the commands received via a serial digital signal transmitted to the second terminal of the RJ-11 connector. The signal processing cable then transmits control signals to the transceiver, with the signals being appropriate to the type of cellular transceiver used, to produce the function requested by the modem's universal command.
Document cited in USPN 4,654,867 issued Mar. 31, 1987 entitled "Millicom Cellular Portable Telephone" article
Excerpt from Digital Fundamentals, 3rd Edition by Thomas L. Floyd, Copyright 1986, pp. 562-569
AT&T Dimsension PBX described in AT&T publication Bell System Practice Section 503-100-130, Issue 3, published Mar. 1981, which related to a multi-botton electronic telephone set
AT&T 208A, Data Set product, Jul. 1975, Circuit Description, CD-1D232-01
"Technical Aspects of Data Communication," John E. McNamara, Jul. 1979, Digital Press
"A Tale of Two Modems," F. R. Derfler Jr., Aug. 21, 1984, PC Magazine
"Advanced Mobile PhoneService: Control Architecture," Z. C. Fluhr & P. T. Porter, Bell System Technical Journal, vol. 58, No. 1, Jan. 1979
"Advanced Mobile Phone Service: A Subscriber Set for the Equipment Test," R. E. Fisher, Bell System Technical Journal, vol. 58, No. 1, Jan. 1979
"Overview of AMPS Mobile Call Processing System," Robert M. Fuller and Fred A. Epler, 1980 Annual Conference of the IEEE Vehicular Technology Society
"Advance Mobile PhoneService," F. H. Blecher, IEEE transactions on Vehicular Technology, vol. VT-29, No. 2, Mar. 1980
"Data Transmission for Mobile Radio," T. Brenig, IEEE Transactions on Vehicular Technology, VT-27, No. 3, Aug. '78
"An 800 Mhz Approach to Underground Data Communications," T. M. Caridi and P. Mighdoll, IEEE 1981 Industry Applications
"ARQ Schemes for Data Transmission in Mobile Radio Systems," R. A. Comroe and D. J. Costello, Jr., IEEE Transactions on Vehicular Technology, vol. VT-33, Aug. 1984
"Optimal Blocklengths for ARQ Error Control Schemes," Joel M. Morris, IEEE Transactions on Communications, vol. COM-27, No. 2, Feb. 1979
"Data Transmissions Over VHF and UHF Land Mobile Radio Channels," P. J. Cadman and R. L. Brewster, IEEE Proceedings vol. 130, Part F, No. 6, Oct. 1983
"Data Signaling Functions for a Cellular Mobile Telephone System," V. Hachenburg, B. D. Holm, and J. I. Smith, IEEE Transactions on Vehicular Technology, vol. VT 26, No. 1, Feb. 1977
"Quality of Service and Bandwidth Efficiency of Cellular Mobile Radio with Variable Bit-Rate Speech Transmission," D. J. Goodman and C. E. W. Sundberg, IEEE Transactions on Vehicular Technology, vol. VT-32, Aug. 1983
AT&T's Dimension PBX described in AT&T publication Bell System Practice Section 503-100-130, Issue 3, published Mar. 1981, which relates to a multi-button electronic telephone set
"R/F Lined Portable Digital Communications Sytem Overview," Proceedings of the National Electronics Conference (1984), Sep. 24-26, Rosemont, Ill., USA, J. Krebs, pp. 402-407
"Portable Computer and Host Talk Over Radio-Frequency Link" Electronics, vol. 56, Aug. 25, 1983, J. Krebs
"Cellnet adds data to Cellular service," International News Telephone Engineer and Management, Nov. 1, 1985
Panasonic's "Easa-Phone" system described in Technical Guide KX-T 30810 for Panasonic's electronic modular switching system; and KX-T 30830 for its associated telephone station
"Low Bit-Rate Speech Coders Applicable in Mobile Satellite Communications Systems", Neviano Dal Degan and Fulvio Russina, CSELT--Centrol Studi e Laboratori Telecommunicazioni S.p.A.--Via G. Reiss Romoli, 274--10148 Torino, Ital