Methods and Systems for Noise and Interference Cancellation

A method for determining a noise cancellation control setting for a noise cancellation device operable to generate an interference compensation signal based on the control setting, the control setting comprising an in-phase parameter and a quadrature parameter, the method comprising:

• receiving a first feedback value indicative of a first level of interference in response to applying the interference compensation signal to an input signal path of an electrical device;
• searching for an improved control setting by sequentially adjusting, one at a time in an alternating manner, the in-phase parameter and the quadrature parameter of the control setting until a stop condition is met;
• for each adjustment to the in-phase parameter and each adjustment to the quadrature parameter:
• generating an updated interference compensation signal based on the adjusted control setting and receiving an updated feedback value in response to applying the updated interference compensation signal to the input signal path;
• determining whether the updated feedback value is preferred over a previous feedback value;
• and
• in response to a determination that the updated feedback value is preferred over the previous feedback value, using the adjusted control setting in a subsequent adjustment;
• and
• in response to the stop condition being met, operating the noise cancellation device using the adjusted control setting.

A method for determining a control setting for a noise cancellation device operative to generate an interference compensation signal based on the control setting, the interference compensation signal operative to suppress interference imposed on a receiver in response to the interference compensation signal being applied to an input signal path of the receiver, the control setting comprising an in-phase parameter and a quadrature parameter, the method comprising:

• receiving a first feedback value indicative of a first level of interference in response to applying the interference compensation signal to the input signal path;
• searching for an improved control setting by sequentially adjusting, one at a time in an alternating manner, the in-phase parameter and the quadrature parameter until a stop condition is met, each adjustment comprising:
• incrementing one of the in-phase parameter and the quadrature parameter to generate a first adjusted control setting, generating a first updated interference compensation signal based on the first adjusted control setting, and receiving a first updated feedback value in response to applying the first updated interference compensation signal to the input signal path;
• decrementing one of the in-phase parameter and the quadrature parameter to generate a second adjusted control setting, generating a second updated interference compensation signal based on the second adjusted control setting, and receiving a second updated feedback value in response to applying the second updated interference compensation signal to the input signal path;
• determining which one of the first updated feedback value, the second feedback value, and a previous feedback value is preferred;
• and
• using the control setting resulting in the one preferred feedback value for a subsequent adjustment.

A method for determining a noise cancellation control setting for generating an interference compensation signal for a cellular telephone application, the method comprising:

• (a) selecting a plurality of initial control settings;
• (b) identifying one of the plurality of initial control settings as preferred for interference suppression;
• (c) selecting subsequent control settings based on performance of the identified control setting;
• (d) identifying one of the subsequent control settings as preferred for interference suppression;
• and
• (e) repeating (c) and (d) until a stopping condition is met.

A method for determining a noise cancellation control setting for generating an interference compensation signal, the method comprising:

• (a) identifying one of a plurality of control settings as preferred for interference suppression, each control setting comprising an in-phase parameter and a quadrature parameter;
• (b) storing the identified control setting;
• (c) generating a first updated control setting and a second updated control setting, the first updated control setting comprising the quadrature parameter of the stored control setting and an incremented in-phase value comprising the in-phase value of the stored control setting incremented by a step size, the second updated control setting comprising the quadrature parameter of the stored control setting and a decremented in-phase value comprising the in-phase value of the stored control setting decremented by the step size;
• (d) receiving a first feedback value corresponding to the first updated control setting and a second feedback value corresponding to the second updated control setting;
• (e) generating an updated in-phase value based on the first updated control setting, the second updated control setting, the first feedback value, and the second feedback value using a dual-slope equation;
• (f) generating a third updated control setting and a fourth updated control setting, the third updated control setting comprising the updated in-phase parameter and an incremented quadrature value comprising the quadrature value of the stored control setting incremented by a step size, the fourth updated control setting comprising the updated in-phase parameter of the stored control setting and a decremented quadrature value comprising the quadrature value of the stored control setting decremented by the step size;
• (g) receiving a third feedback value corresponding to the third updated control setting and a fourth feedback value corresponding to the fourth updated control setting;
• (h) generating an updated quadrature value based on the third updated control setting, the fourth updated control setting, the third feedback value, and the fourth feedback value using a dual-slope equation;
• (i) reducing the value of the step size;
• and
• (h) repeating (b) through (i) until a stop condition is met.

A method for determining a control setting for each of a plurality of noise cancellation devices, the plurality of noise cancellation devices configured to generate an interference compensation signal based on the control setting, the interference compensation signal operative to suppress interference imposed on a receiver in response to the interference compensation signal being applied to an input signal path of the receiver, each control setting comprising an in-phase value and a quadrature value, the method comprising:

• creating a combined control setting for the noise cancellation devices comprising a combined in-phase value and a combined quadrature value, the combined in-phase value comprising the in-phase value for each control setting arranged in a sequence, the combined quadrature value comprising the quadrature value for each control setting arranged in a sequence;
• and
• searching for a preferred combined control setting by modifying the combined control setting according to at least one computer program until a stop condition is met;
• for each modification to the combined control setting:
• applying, to each noise cancellation device, the in-phase value and quadrature value of the modified combined control setting corresponding to the noise cancellation device;
• generating an interference compensation signal by the noise cancellation devices;
• receiving a feedback value indicative of a level of the interference in response to applying the interference compensation signal to the input signal path;
• and
• storing the feedback value;
• and
• in response to the stop condition being met, identifying which one of the stored feedback values results in preferred suppression of interference imposed on the receiver.

A method for determining a control setting for each of a plurality of noise cancellation devices, the plurality of noise cancellation devices configured to generate an interference compensation signal based on the respective control setting, the interference compensation signal operative to suppress interference imposed on a receiver in response to the interference compensation signal being applied to an input signal path of the receiver, the method comprising:

• (a) applying the respective control setting to each of the plurality of noise cancellation devices;
• (b) identifying an improved control setting for one of the plurality of noise cancellation devices by executing a computer program on the one noise cancellation device while holding the control setting for each other noise cancellation device constant;
• (c) operating the one noise cancellation device using the improved control setting for the one noise cancellation device;
• and
• (d) repeating (b) and (c) for each of the plurality of noise cancellation devices.

A method for tuning a control setting for each of a plurality of noise cancellation devices operative to suppress noise across a given frequency bandwidth, the method comprising:

• identifying a first control setting for a first noise cancellation device by executing at least one computer program for a first portion of the frequency bandwidth;
• identifying a second control setting for a second noise cancellation device by executing at least one computer program for a second portion of the frequency bandwidth;
• storing the first control setting and the second control setting;
• and
• operating the first noise cancellation device according to the first control setting and operating the second noise cancellation device according to the second control setting.

A cellular telephone system, comprising:

• an interference compensation circuit for generating an interference compensation signal based on a noise cancellation control setting, the interference compensation circuit configured to:
• (a) select a plurality of initial control settings;
• (b) identify one of the plurality of initial control settings as preferred for interference suppression;
• (c) select subsequent control settings based on performance of the identified control setting;
• (d) identify one of the subsequent control settings as preferred for interference suppression;
• and
• (e) repeat (c) and (d) until a stopping condition is met.