# US 9,753,071 B1 · System and method for improved resolution pulsed radio frequency (RF) measurements with phase coherence > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,753,071 B1 - Document ID: US9753071B1 - Status: Granted - Kind: B1 - Application number: 14/213,291 - Filed: 2014-03-14 - Granted: 2017-09-05 - Earliest claimed: 2013-03-15 - Assignees: Anritsu Corporation - Applicants: Anritsu Company - Inventors: Jon S. Martens - Web page: https://patentgrep.com/patent/US9753071B1 ## CPC - G01R 27/28: Measuring attenuation, gain, phase shift or derived characteristics of electric four pole networks, i.e. two-port networks; Measuring transient response (in line transmission systems H04B3/46) - G01R 27/32: in circuits having distributed constants {, e.g. having very long conductors or involving high frequencies} - G01R 31/2822: {of microwave or radiofrequency circuits (of attenuation, gain, e.g. using network analyzers G01R27/28)} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract A method for obtaining improved resolution pulsed radio frequency (RF) measurements with phase coherence for a device under test (DUT) using a vector network analyzer (VNA) includes generating a pulsed RF test signal, transmitting the pulsed RF test signal to the DUT and receiving a signal from the DUT at the VNA in response to the pulsed RF test signal. An intermediate frequency (IF) signal is generated using a local oscillator (LO) signal. A phase of the LO signal is shifted by a prescribed amount while generating the IF signal. The IF signal is then sampled over multiple pulses and measurements are constructed from the measurements. A discrete Fourier transform (DFT) is then applied to the constructed measurements. ## Claims ### Claim 1 A method for obtaining radio frequency (RF) measurements for a device under test (DUT) using a vector network analyzer (VNA), comprising: generating a pulsed RF test signal; transmitting the pulsed RF test signal to the DUT; receiving a RF signal in response to the pulsed RF test signal; generating an intermediate frequency (IF) signal by downconverting the RF signal received in response to the pulsed RF test signal using a local oscillator (LO) signal; shifting a phase per unit time change of the LO signal by a prescribed amount over multiple pulses of the pulsed RF test signal for a frequency of the pulsed RF test signal; sampling the generated IF signal at each of the multiple pulses to obtain a sample set for the frequency of the pulsed RF test signal; constructing measurements from the sample set; and applying a discrete Fourier transform (DFT) on the measurements constructed from the sample set. ### Claim 2 (depends on 1) The method of claim 1, wherein the prescribed amount of shift in the phase per unit time change of the LO signal is 2π. ### Claim 3 (depends on 1) The method of claim 1, wherein the discrete Fourier transform applied to the constructed measurements a short-time discrete Fourier transform (STDFT). ### Claim 4 (depends on 1) The method of claim 1, wherein when the phase per unit time change of the LO signal is shifted by the prescribed amount, an analog-to-digital converter (ADC) clock for generating the pulsed RF test signal is maintained at the same rate. ### Claim 5 A system for obtaining radio frequency (RF) measurements for a device under test (DUT), comprising: a pulse modulator connectable with the DUT; a vector network analyzer (VNA) connectable with the DUT and the pulse modulator; wherein the VNA includes a processor and a non-transitory computer readable storage medium having instructions thereon that when executed cause the system to generate a pulsed RF test signal; transmit the pulsed RF test signal to the DUT; receive a RF signal in response to the pulsed RF test signal; generate an intermediate frequency (IF) signal by downconverting the RF signal received in response to the pulsed RF test signal using a local oscillator (LO) signal; shift a phase per unit time change of the LO signal by a prescribed amount over multiple pulses of the pulsed RF test signal for a frequency of the pulsed RF test signal; sample the generated IF signal at each of the multiple pulses to obtain a sample set for the frequency of the pulsed RF test signal; construct measurements from the sample set; and apply a discrete Fourier transform (DFT) on the measurements constructed from the sample set. ### Claim 6 (depends on 5) The system of claim 5, wherein the prescribed amount of shift in phase per unit time change of the LO signal is 2π. ### Claim 7 (depends on 5) The system of claim 5, wherein the non-transitory computer readable storage medium further has instructions thereon that when executed cause the system to apply a short-time discrete Fourier transform (STDFT) to the constructed measurements. ### Claim 8 (depends on 5) The system of claim 5, wherein when the phase per unit time change of the LO signal is shifted by the prescribed amount an analog-to-digital converter (ADC) clock for generating the pulsed RF test signal is maintained at the same rate. ### Claim 9 A non-transitory computer readable storage medium, including instructions stored thereon which when read and executed by one or more computers cause the one or more computers to perform the steps comprising: generating a pulsed RF test signal; transmitting the pulsed RF test signal to a device under test (DUT); receiving a RF signal in response to the pulsed RF test signal; generating an intermediate frequency (IF) signal by downconverting the RF signal received in response to the pulsed RF test signal using a local oscillator (LO) signal; shifting a phase per unit time change of the LO signal by a prescribed amount over multiple pulses of the pulsed RF test signal for a frequency of the pulsed RF test signal; sampling the generated IF signal at each of the multiple pulses to obtain a sample set for the frequency of the pulsed RF test signal; constructing measurements from the sample set; and applying a discrete Fourier transform (DFT) on the measurements constructed from the sample set. ### Claim 10 (depends on 9) The non-transitory computer readable storage medium of claim 9, wherein the prescribed amount of shift in phase per unit time change of the LO signal is 2π. ### Claim 11 (depends on 9) The non-transitory computer readable storage medium of claim 9, wherein the DFT applied is a short-time discrete Fourier transform (STDFT). ### Claim 12 (depends on 9) The non-transitory computer readable storage medium of claim 9, wherein when the phase per unit time change of the LO signal is shifted by the prescribed amount an analog-to-digital converter (ADC) clock for generating the pulsed RF test signal is maintained at the same rate.