Digital conference system

A digital conference system for providing conference conversations among selected groups of stations in a communications system, said system comprising in combination:

• a. a plurality of stations for generating speaker signals and for generating conference control signals, each of said stations responsive to a listener address signal for receiving selected groups of listener output signals;
• b. programmable list processor means connected to receive said conference control signals and responsive thereto for generating memory address signals and control signals and including attenuator means for generating an attenuation signal;
• c. memory means connected to receive said speaker signals and for sequentially storing and periodically updating samples of said speaker signals, said memory means also connected to receive said memory address signals and responsive thereto for generating a series of listener output pulses;
• d. multiplier means coupled to said memory means and being responsive to said attenuation signal for generating attenuated listener output pulses;
• e. accumulator means coupled to said multiplier means and responsive to said control signals for accumulating selected groups of attenuated listener output pulses and for generating said listener output signals;
• and
• f. listener address means responsive to said control signals for generating said listener address signal;
• whereby, selected groups of said listener output signals received by a station are representative of the desired conference conversation to be heard at said station and the amplitude of each conference conversation being monitored by an operator at said station can be controlled by said operator.

A digital conference system for providing conference conversations among selected groups of stations in a communications system, said system comprising in combination:

• a. a plurality of stations for generating digital speaker signals and for generating conference control signals, each of said stations responsive to a listener address signal for receiving selected groups of a listener output signal, each of said plurality of stations including:
• 1. an analog to digital converter for converting an analog input signal from a speaker to said digital speaker signals;
• 2. a digital to analog converter for converting selected groups of said digital listener signals into an analog output signal for transmission to a listener;
• and
• 3. control means for generating said conference control signals;
• b. programmable list processor means connected to receive said conference control signals and responsive thereto for generating memory address signals and control signals, said programmable list processor means including:
• 1. a recirculating shift register for generating said memory address signals and said control signals;
• and
• 2. a processor means responsive to said conference control signals for rearranging the data content of said shift register in accordance with a predetermined encoding scheme upon receiving an updated conference control signal;
• c. memory means connected to receive said digital speaker signals and for sequentially storing and periodically updating samples of said digital speaker signals, said memory means also connected to receive said memory address signals and responsive thereto for generating a series of listener output pulses;
• said memory means including:
• 1. sampling means for sequentially sampling said digital speaker signals;
• and
• 2. random access memory means for storing and periodically updating samples of said digital speaker signals received from said sampling means and for generating a series of listener output pulses in response to said memory address signals;
• d. accumulator means coupled to said memory means and responsive to said control signals for accumulating selected groups of said listener output pulses and for generating said listener output signals;
• and
• e. listener address means responsive to said control signals for generating said listener address signals;
• whereby, the selected groups of listener output signals received by a station are representative of the desired conference conversation to be heard at said station.

A method for providing conference conversations among selected groups of stations in a communication system, said method comprising the steps of:

• a. generating conference control signals designating which ones of a plurality of stations are to be received by a particular station;
• b. transmitting the conference control signals to a processor means;
• c. generating speaker signals representing the words spoken by an operator at each of said plurality of stations;
• d. transmitting said speaker signals to said processor means;
• e. generating a recirculating train of memory address signals and conference control signals in repetitive frames in response to said conference control signals;
• f. sequentially storing and periodically updating once during each frame samples of said speaker signals;
• g. generating a listener output pulse in response to each memory address signal;
• h. accumulating selected groups of listener output pulses and generating a train of listener output signals in response to said control signals, each listener output signal being representative of a desired conference conversation to be heard at a predetermined station;
• i. generating a listener address signal in response to said control signals for designating a predetermined station to receive each listener output signal;
• j. transmitting said listener output signals and said listener address signals to said plurality of stations;
• and
• k. receiving selected listener output signals at predetermined stations in response to said listener address signals;
• whereby, the listener output signals received by a predetermined station are representative of the desired conference conversation to be heard at said station.