# US 2019/0317211 A1 · Pseudo random frequency sonar ping generation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0317211 A1 - Document ID: US20190317211A1 - Status: Published application - Kind: A1 - Application number: 15/953,423 - Filed: 2018-04-14 - Published: 2019-10-17 - Earliest claimed: 2018-04-14 - Assignees: Coda Octopus Group, Inc. - Inventors: Martyn Sloss - Web page: https://patentgrep.com/patent/US20190317211A1 ## CPC - G01S 7/5273: {using digital techniques} - G01S 15/102: {using transmission of pulses having some particular characteristics} - G01S 15/104: {wherein the transmitted pulses use a frequency- or phase-modulated carrier wave} - G01S 15/107: {using frequency agility of carrier wave} - G01S 15/89: for mapping or imaging - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES ## Abstract In a sonar system using a large array multielement sonar detector to detect reflected signals sent out by a sonar ping generator, the sent out sonar ping generator sends out varying frequency sonar signals during each ping, where the frequency is neither monotonically increasing or monotonically decreasing. ## Claims ### Claim 1 A method, comprising: a) insonifying a volume of fluid with one or a series of sonar pings, wherein the volume of fluid contains zero or more objects, wherein at least one of the one or a series of sonar pings has a frequency which changes significantly during the sonar ping, and wherein the frequency change is neither monotonically increasing nor monotonically decreasing. ### Claim 2 (depends on 1) The method of claim 1, further comprising; b) receiving sonar signals from the at least one of the one or a series of sonar pings reflected from the zero or more objects, the sonar signals wherein the sonar signals are received by a large array of hydrophones, and wherein each of the large array of hydrophones produces an analog voltage vs time electrical signal, wherein the analog voltage vs time electrical signal comprises a first set of raw data points which show the phase and the intensity of the sonar signal received by each of the large array of hydrophones, then c) converting the first set of raw data points to a second set of raw data points, the second set of raw data points comprising digital representations of the phase of the sonar signals reflected from the zero or more objects and received by each hydrophone in the large array of hydrophones, wherein the second set of raw data points comprises an n bit number for each hydrophone, and wherein n is a positive integer less than 3. ### Claim 3 (depends on 1) The method of claim 1, further comprising; b) receiving sonar signals from the at least one of the one or a series of sonar pings reflected from the zero or more objects, the sonar signals wherein the sonar signals are received by a large array of hydrophones, and wherein each of the large array of hydrophones produces an analog voltage vs time electrical signal, wherein the analog voltage vs time electrical signal comprises a first set of raw data points which show the phase and the intensity of the sonar signal received by each of the large array of hydrophones, then c) converting the first set of raw data points to a third set of raw data points, the third set of raw data points comprising digital representations of the phase and intensity of the sonar signals received by each hydrophone, wherein the raw data from a single ping is recorded as a set of pairs of digital numbers, each digital number recorded by one of the large array of hydrophones, and wherein pairs of digital numbers are recorded for each time slice of the single ping, and wherein one of each pair of digital numbers is a measure of the returned sonar intensity, and wherein the other of each pair of digital numbers is a measure of the phase of the returned sonar signal. ### Claim 4 (depends on 1) The method of claim 1, at least one part of the at least one of the one or a series of sonar pings has a frequency which is at least 10% greater than the frequency of another part of the same sonar ping. ### Claim 5 (depends on 4) The method of claim 4, at least one part of the at least one of the one or a series of sonar pings has a frequency which is at least 50% greater than the frequency of another part of the same sonar ping. ### Claim 6 A method, comprising: a) insonifying a volume of fluid with at least one or a series of sonar pings, wherein the volume of fluid contains zero or more objects, wherein at least one of the one or a series of sonar pings has a pseudo random frequency pattern, wherein the pseudo random frequency pattern is not a uniform frequency nor a monotonically increasing frequency nor a monotonically decreasing frequency. ### Claim 7 (depends on 6) The method of claim 6, wherein the pseudo random frequency pattern is chosen from a set of pseudo random frequency patterns, wherein set of pseudo random frequency patterns is generated by running computer models of pings of possible of frequency patterns impinging on various collections of objects at various ranges and angles with respect to an array detector for detecting sonar signals reflected from the various collections of objects, and then analyzing the model results and choosing the set of pseudo random frequency patterns according to a criterion. ### Claim 8 (depends on 7) The method of claim 7, wherein one criterion is that the convolution of a pseudo random frequency pattern of the insonifying sonar ping with the received sonar signal returns a convolution curve with a peak, wherein the area under the peak is greater than a determined area. ### Claim 9 (depends on 7) The method of claim 7, wherein one criterion is that the convolution curve returned by convolving sent out signals of one member of the set of chosen frequency patterns with received signals of another member of the same set has no peaks wherein the area under the peak is greater than a determined area. ### Claim 10 (depends on 9) The method of claim 9, wherein step a) further comprises; insonifying the volume of fluid with at least two sonar pings, wherein the patterns of each of the at least two sonar pings are different patterns chosen from the set of pseudo random frequency patterns, and wherein the at least two sonar pings are sent out at such a time that reflected sonar signals from the at least two sonar pings arrive as overlapping signals at an array detector for detecting sonar signals. ### Claim 11 A method, comprising: a) insonifying a volume of fluid with at least one or a series of sonar pings, wherein the volume of fluid contains zero or more objects, wherein at least one of the one or a series of sonar pings has a pseudo random frequency pattern. ### Claim 12 (depends on 11) The method of claim 11, further comprising; b) receiving sonar signals from the at least one of the one or a series of sonar pings reflected from the zero or more objects, the sonar signals wherein the sonar signals are received by a large array of hydrophones, and wherein each of the large array of hydrophones produces an analog voltage vs time electrical signal, wherein the analog voltage vs time electrical signal comprises a first set of raw data points which show the phase and the intensity of the sonar signal received by each of the large array of hydrophones, then c) converting the first set of raw data points to a second set of raw data points, the second set of raw data points comprising digital representations of at least the phase of the sonar signals reflected from the zero or more objects and received by each hydrophone in the large array of hydrophones.