Pulsed communication system

• US 5,087,982 A
• Filed: 11/14/1990
• Issued: 02/11/1992
• Est. Priority Date: 11/14/1990
• Status: Expired due to Fees

• Current Assignee: Mesler Incorporated
• Original Assignee: Inter Innovation Lefebure Manufacturing Corporation
• Inventors: Smothers, Steven W.
• Primary Examiner(s): Coles, Sr., Edward L.
• Assistant Examiner(s): PASCAL, LESLIE C
• Application Number:
  US07/613,092
• Time in Patent Office: 454 Days
• Field of Search: 370/1, 370/4, 370/3, 455/601, 455/603, 455/606, 455/607, 455/608, 455/617, 455/618, 455/619, 359/137, 359/172-186
• US Class Current: 398/118
• CPC Class Codes: H04J 14/08 Time-division multiplex systems

Abstract

An optical communication system includes a stationary master unit which is adapted to receive through a wired communication bus a plurality of separate communication input signals and communicate a corresponding plurality of separate communication output signals. The master unit converts the input signals to pulsed signals and optically transmits the pulsed signals corresponding to each of the separate signals during designated time slots to one of a plurality of separate communication units which preferably are portable units. The portable units reconvert the received pulsed signals to signals corresponding to the original communication signals. Each of the portable units also receives individually separate communication signals, converts the received communication signals to pulsed signals and optically transmits the pulsed signals to the master unit in the same manner. The master unit converts the received pulsed signals to communication output signals and communicates them over the bus to a designated output terminal. Range extending units may be coupled to the master unit. The disclosed optical system is particularly adaptable to improve existing communication systems at drive-up windows of banks or similar installations.

Claims

1. A pulsed communication system comprising:

means for generating consecutive cycles, each cycle defining a plurality of sequential time slots including a plurality of first data time slots and a plurality of second data time slots;

a plurality of first communication units each first unit including a communication port having an input and an output terminal and means for receiving from the input terminal a communication in the form of first type signals and for transferring to the output terminal a communication in the form of first type signals, means for converting the received first type signals to a sequence of pulses and for transmitting the converted first type signals as pulsed signals, one pulse during each cycle and during a predetermined one of the second data time slots thereof, means for receiving pulsed signals, one pulse during each cycle and during a predetermined one of the first data time slots thereof, and means for converting the received pulsed signals to first type signals and for transferring the received pulsed signals as first type signals to the output terminal of each first communication unit; and

a master unit including an interface having a plurality of separate input and output ports, means for receiving from each input port a separate communication in the form of said first type signals and for transferring to each output port a separate communication in the form of said first type signals, means for converting the received first type signals to a sequence of pulses and for transmitting the converted first type signals as pulsed signals, one pulse of each separate communication during a predetermined first data time slot of each cycle to correspond to a predetermined first data time slot for receipt of said pulse by a designated one of said first units, and means for receiving a plurality of separate communications independently of each other from the first communication units in the form of said pulsed signals, one pulse of each separate communication during a predetermined second data time slot indicative of transmission from a predetermined one of the first units, means for converting said pulsed signals to separate communications of first type signals and for transferring the separate communications to a predetermined one of the output ports.

2. The system according to claim 1, wherein the system is an optical, pulsed system and the means of the first units and of the master unit for transmitting pulsed signals comprises light emitting diodes, and the means of the first units and of the master unit for receiving pulsed signals comprises photosensor diodes.

3. The system according to claim 2, wherein the system further includes at least one extension unit electrically coupled to the master unit for extending effective optical transmission and reception ranges of the master unit.

4. The system according to claim 1, wherein the means for generating consecutive cycles of a plurality of sequential, timed signals comprises a clock and counter disposed in each of the first units and in the master unit, the master unit further comprising means for generating and transmitting a sync pulse during an initial time slot in each cycle and each of the first units comprises means for receiving said sync pulse and for synchronizing the clock and counter of the respective first unit in response thereto.

5. The system according to claim 4, wherein the first and second data time slots are alternately arranged in a sequence in which each second data time slot follows one of the first data time slots in each cycle.

6. The system according to claim 4, wherein a second time slot in each cycle following the initial time slot in each cycle is an idle time, said idle time following the transmission by the master unit of the sync pulse and preceding the first and second data time slots.

7. The system according to claim 6, wherein the plurality of first units are three first units, and each such cycle of timed signals defines eight time slots, including said initial time slot for transmission and reception of said sync pulse, said second time slot corresponding to said idle time, and three first and second data time slots following said idle time.

8. The system according to claim 6, wherein the system is an optical, pulsed system and the means of the first units and of the master unit for transmitting pulsed signals comprises light emitting diodes, and the means of the first units and of the master unit for receiving pulsed signals comprises at least one photosensor diode in each of the units.

9. The system according to claim 8, wherein the master unit comprises means for delaying the transmission of the pulsed signals by a predetermined period within the respective first time slots, the period corresponding to a period by which the synchronized cycle of the first units is delayed with respect to the cycle of the master unit.

10. The system according to claim 8, wherein the light emitting diodes of the master unit are spaced circumferentially about the master unit to transmit the pulsed signals substantially equally in all directions with respect to the master unit, and wherein the means of the master unit for generating and transmitting a sync pulse includes a plurality of circumferentially spaced light emitting diodes separate and distinct from the light emitting diodes for transmitting the pulsed signals.

11. The system according to claim 8, wherein the means of the first units and of the master unit for receiving pulsed signals comprises a pre-amp coupled to the photosensor diode, and a switch operated during transmission of pulsed signals from the respective first units and master unit for blocking the received pulsed signals from being amplified upon being received by the photosensor diodes of the first and master transmitting units.

12. The system according to claim 11, wherein the system further includes at least one extension unit electrically coupled to the master unit and spaced from the master unit for extending effective optical transmission and reception ranges of the master unit, said extension unit including means for transmitting the converted first type signals as pulsed signals, one pulse of each separate communication during a predetermined first data time slot of each cycle to correspond to a predetermined first data time slot for receipt of said pulse by a designated one of said first units, and means for receiving a plurality of separate communications independently of each other from the first communication units in the form of said pulsed signals, one pulse of each separate communication during a predetermined data second time slot indicative of transmission from a predetermined one of the first units, said receiving means of said extension unit including a pre-amp coupled to a photosensor diode, and a switch operated during transmission of pulsed signals from said extension unit for blocking such pulsed signals from being amplified upon being received by the photosensor diode of said extension unit.

13. The system according to claim 11, wherein the first units comprise means for detecting the strength of the received pulsed signals relative to a predetermined threshold, and means, operative in response to a detected absence of a signal exceeding the predetermined threshold, for disabling the means for transferring the received pulsed signals as first type signals to the output terminal of such first communication units.

14. The system according to claim 13, wherein the first units comprise means for detecting the presence of communicated information in the received pulsed signals, and means, operative in response to a detected absence of communicated information in the received pulsed signals, for disabling the means for tranferring the received pulsed signals as first type signals to the output terminal of such first communication units.

15. The system according to claim 14 wherein the first units comprise first, second and third cases, both the first and second cases comprising said light emitting diodes, said pre-amp and said photosensor diode.

16. A pulsed optical communication system including a master unit and a plurality of individual units, each individual unit to communicate with the master unit independently of any other individual unit over a common optical transmission link, the system comprising:

means for synchronizing the individual units and the master unit to operate on a time cycle having a plurality of time slots, the time slots including first type time slots for communication of a single data pulse per time slot during a designated first type time slot from the master unit to a respectively designated one of the individual units, and second type time slots for communication of a single data pulse per time slot during a designated second type time slot from a designated one of the individual units to the master unit;

the master unit including signal input means for accepting simultaneously a plurality of distinct messages of first type signals, each of the messages designated to be communicated to a selected one of the individual units, means for converting during respective ones of the first type time slots the first type signals to pulse width modulated pulsed signals, and means for transmitting the pulsed signals optically, one pulse during each respectively designated ones of the first type time slots of each time cycle for reception by a respectively designated one of the individual units, the master unit further including means for receiving during designated ones of the second type time slots pulse width modified optically pulsed signals from respectively designated ones of the individual units, means for converting the received pulsed signals to the first type signals, a plurality of distinct output means for simultaneously communicating the converted first type signals as a plurality of distinct messages independently of each other at each of the output means, and means for selectively applying the converted first type signals to respective ones of the output means in accordance with the receipt of the pulsed signals during a designated one of the second type time slots; and

each of the individual units including means for converting during a designated one of the second type time slots messages of the first type signals to pulse width modulated pulsed signals, and means for transmitting the pulsed signals optically, one pulse each during a designated one of the second type time slots of each time cycle for reception by the master unit, means for receiving from the master unit optically pulsed signals, a single pulsed signal during each designated one of the first type time slots in each time slot, and means for converting the received pulsed signals to a message of first type signals.

17. The system according to claim 16, wherein the means for synchronizing the individual units and the master unit comprises means for generating and transmitting a sync pulse at the beginning of each cycle, the sync pulse generating means disposed in the master unit, and means disposed in each of the individual units for receiving the sync pulse and for synchronizing the time cycle of first and second type time slots to the sync pulse;

and wherein the master unit includes means for delaying the transmission of each of the pulsed signals transmitted during the first type time slots by a predetermined time period with respect to the beginning of each respective time slot.

18. The system according to claim 16, wherein the first type signals are electrical analog signals, and the means for converting the analog signals to pulse width modified pulsed signals comprises means for sampling during a designated time slot of each cycle the magnitude of a designated one of the analog signals and for converting the sampled magnitude into a pulse width modulated electrical signal.

19. The system according to claim 16, wherein the means for synchronizing the individual units and the master unit comprises means for generating and transmitting a sync pulse at the beginning of each cycle, the sync pulse generating means disposed in the master unit, and wherein the means for transmitting the sync pulse comprises optical transmission means separate from the means in the master unit for transmitting the pulsed signals optically.