Intelligent fiberoptic receivers and method of operating and manufacturing the same

A fiberoptic receiver for receiving optical pulses from a communications network, the receiver comprising:

• an optical-to-electrical conversion element having at least one bias condition;
• a gain circuit coupled to the optical-to-electrical conversion element, the gain circuit having at least one gain setting;
• at least one sensor that monitors one or more operating conditions of the receiver and provides monitored values for the one or more operating conditions;
• circuitry coupled to the at least one sensor, wherein the circuitry accesses one or more locations of a non-volatile memory, the locations corresponding to the monitored values and storing data indicative of settings of one or more operating parameters of the receiver, the one or more operating parameters include the at least one bias condition and the at least one gain setting;
• and
• circuitry that implements at least one control loop that adjusts selected ones of the operating parameters of the receiver in response to the data.

A fiberoptic receiver for receiving optical pulses from a communications network, the receiver comprising:

• an optical-to-electrical conversion element that draws a current that is a function of the optical power of the received pulses;
• at least one sensor that monitors one or more conditions of an environment in which the receiver operates and that thereby obtains values for the one or more conditions;
• circuitry that accesses one or more locations of a non-volatile memory, the locations corresponding to the values and storing data from which can be determined one or more parameters suitable for controlling the operation of the receiver when the monitored conditions have the values, said one or more parameters including a value of a bias voltage applied to the optical-to-electrical conversion element;
• and
• a first control loop that reduces the bias voltage applied to the optical-to-electrical conversion element whenever the current drawn by the optical-to-electrical conversion element exceeds a first activation current level, the first control loop having a first response time.

A method of calibrating a fiberoptic receiver that comprises an optical-to-electrical conversion element receiving optical pulses from a communications network during normal operation of the receiver, a bias voltage being applied to the optical-to-electrical conversion element, the method comprising, for each particular environment in a set of environments in which the receiver could be deployed during normal operation, the steps of:

• placing the receiver in the particular environment;
• determining a best bias voltage parameter for the optical-to-electrical conversion element of the receiver when operated in the particular environment, the best bias voltage parameter being determined by the steps of
• for each particular voltage from a first set of voltages spanning a first voltage range by a first increment, setting the bias voltage to the particular voltage, transmitting known data to the receiver, and measuring an error rate for the receiver,
• determining a first voltage from the first set of voltages such that the measured error rate for the first voltage is smaller than the error rate measured for any other voltage from the first set of voltages,
• for each particular voltage from a second set of voltages spanning a second voltage range that is smaller than the first voltage range by a second increment that is smaller than the first increment, setting the bias voltage to the particular voltage, transmitting known data to the receiver, and measuring an error rate for the receiver, the second voltage range being substantially centered around the first voltage, and
• determining that the best bias voltage parameter for the conversion element when operated in the particular environment is a second voltage from the second set of voltages, wherein the measured error rate for the second voltage from the second set of voltages is smaller than the error rate measured for any other voltage from the second set of voltages;
• and
• storing the best bias voltage parameter in a memory at a location corresponding to the particular environment, wherein during normal operation of the receiver in an operating environment the memory is accessed at one or more locations corresponding to the operating environment in order to obtain data from which the best bias voltage parameter of the receiver when operated in the operating environment can be determined.