Increasing ultrasonic flow measurement update rate

An apparatus, comprising:

• a first ultrasonic transmitter;
• a first ultrasonic receiver;
• and
• a controller coupled to the first ultrasonic transmitter and the first ultrasonic receiver, the controller having a controller input and a measurement output and configured to:
• receive a first signal at the controller input, the first signal representing a first time of transmission of a first set of ultrasonic pulses by a second ultrasonic transmitter;
• at a second time, receive the first set of ultrasonic pulses using the first ultrasonic receiver;
• based on the first time and the second time, determine an expected arrival time of a first echo of multiple echoes of the first set of ultrasonic pulses at the first ultrasonic receiver;
• determine a third time of transmission of a second set of ultrasonic pulses, in which the third time precedes the expected arrival time;
• at the third time, transmit a second set of ultrasonic pulses using the first ultrasonic transmitter;
• and
• provide a second signal representing a flow rate measurement at the measurement output based on the first, second, and third times.

A method, comprising:

• at a first time, transmitting a first set of ultrasonic pulses from a first location;
• at a second time, receiving the first set of ultrasonic pulses at a second location;
• at a third time, transmitting a second set of ultrasonic pulses from the second location;
• at a fourth time, receiving a first echo of multiple echoes of the first set of ultrasonic pulses at the second location, in which the third time is the same as the first time, or is between the second time and the fourth time;
• at a fifth time, receiving the second set of ultrasonic pulses at the first location;
• and
• providing a flow rate measurement between the first and second locations based on the first time, the second time, the third time, and the fifth time.

A non-transitory computer readable medium storing instructions that, when executed by processor circuitry, cause the processor circuitry to control a first ultrasonic transmitter and a first ultrasonic receiver at a first location, a second ultrasonic transmitter and a second ultrasonic receiver at a second location to:

• at a first time, transmit a first set of ultrasonic pulses from a first location;
• at a second time, receive the first set of ultrasonic pulses at a second location;
• at a third time, transmit a second set of ultrasonic pulses from the second location;
• at a fourth time, receive a first echo of multiple echoes of the first set of ultrasonic pulses at the second location, in which the third time is the same as the first time, or is between the second time and the fourth time;
• at a fifth time, receive the second set of ultrasonic pulses at the first location;
• and
• provide a flow rate measurement between the first and second locations based on the first time, the second time, the third time, and the fifth time.