UWB radar measurement evaluation method and arrangement

1 . A method of evaluating radar measurement data, the method comprising:

forming plural channel impulse response profiles from radar signals received across plural sample time intervals, the radar signals being received due to reflection or interaction of plural ultra-wideband (UWB) radar radiation pulses transmitted towards a target;

identifying, in each of the plural channel impulse response profiles, one sample time interval of the plural sample time intervals as a target sample time interval in which the received radar signals are due to reflection from the target;

evaluating radar signals of interest in the target sample time interval, each of the radar signals of interest defined as respective magnitude and phase of the plural channel impulse response profiles in the target sample time interval, in order to determine a phase of a target contribution of one or more of the radar signals of interest to a total radar signal of interest comprising the radar signals of interest; and

determining at least one of a location or movement information of the target based on the phase of the target contribution.

2 . The method according to claim 1 ,

wherein evaluating the radar signals of interest comprises:

determining, for each of the radar signals of interest, an associated phase of the target contribution to the respective radar signal of interest,

wherein determining the location or movement information of the target is based on the phases of the target contribution for all of the radar signals of interest,

wherein each channel impulse response profile defines a magnitude and phase of the received radar signals for a subset of the plural sample time intervals.

3 . The method according to claim 1 ,

wherein determining the location or movement information of the target comprises:

using the target sample time interval to derive a target location interval; and

using at least one phase of the target contribution to estimate one of a movement or a position of the target within the target location interval.

4 . The method according to claim 1 ,

wherein each of the radar signals of interest comprises:

a crosstalk contribution, being a contribution due to back coupling or crosstalk between a transmitter, transmitting the plural UWB radar radiation pulses, and a receiver, receiving the radar signals; and

the target contribution, being a contribution due to interaction or reflection of the transmitted plural UWB radar radiation pulses at the target.

5 . The method according to claim 4 , wherein evaluating the radar signals of interest comprises:

determining the crosstalk contribution by processing the received radar signals; and

subtracting the crosstalk contribution from each of the total radar signals of interest, in order to derive the target contribution for each of the radar signals of interest, each target contribution comprising at least a target phase and a target magnitude.

6 . The method according to claim 4 ,

wherein the crosstalk contribution is determined by averaging the radar signals of interest over an averaging time range to generate an approximate crosstalk contribution,

wherein the approximate crosstalk contribution is subtracted from the radar signals of interest within the averaging time range, in order to derive approximate target contributions within the averaging time range, each approximate target contribution comprising at least an approximate target phase and an approximate target magnitude.

7 . The method according to claim 4 , wherein determining the crosstalk contribution by processing the radar signals of interest comprises:

forming cumulative phases of the approximate target phases over different cumulative phase time ranges; and

determining a cumulative phase time range of interest, where the cumulative phase of the approximate target phases satisfies a criterium.

8 . The method according to claim 7 , comprising, if the cumulative phase of the approximate target phases does not satisfy the criterium:

acquiring further radar measurement data and determining further radar signals of interest; and

determining further cumulative phase time ranges of interest, until a further cumulative phase time range of interest satisfies the criterium.

9 . The method according to claim 7 , wherein determining the crosstalk contribution further comprises:

fitting the radar signals of interest across the cumulative phase time range of interest onto a predetermined curve shape being associated with a curve center; and

setting the crosstalk contribution to the curve center.

10 . The method according to claim 1 ,

wherein if the target phase indicates that target has moved such that its radar signals are received in another target sample time interval, the method comprises:

evaluating other radar signals of interest, associated with the other target sample time interval;

determining another crosstalk contribution in the other radar signals of interest by one or more of approximation or curve shape fitting;

deriving other target phases; and

deriving another target location or movement based on the other target time sample interval and the other target phases.

11 . The method according to claim 1 , wherein identifying the target sample time interval comprises:

forming at least one difference between the plural channel impulse response profiles relative to a reference impulse response profile or forming an average over the plural channel impulse response profiles; and

performing peak finding in the at least one difference or in the average.

12 . The method according to claim 1 ,

wherein a channel impulse response profile of the plural channel impulse response profiles is formed as an average of received signals in accordance with a code according to which the pulses are transmitted;

wherein forming the plural channel impulse response profiles from the received radar signals comprises at least one of:

removing a carrier radiation contribution; or

demodulating the received radar signals, in order to extract in-phase components and quadrature components.

13 . The method according to claim 1 , wherein:

the target is moving in one direction or is moving back and forth;

the radar signals are received at a rate between 0.5 and 2 GHz; or

a pulse width of the transmitted plural UWB radar radiation pulses is between 0.5 ns and 2 ns.

14 . The method of claim 1 , further comprising:

transmitting the plural UWB radar radiation pulses; and

receiving, during the plural sample time intervals, the radar signals due to reflection or interaction of the transmitted plural UWB radar radiation pulses at the target.

15 . An arrangement for evaluating a radar measurement data, the arrangement comprising:

a transmitter configured to transmit plural ultra-wideband (UWB) radar radiation pulses towards a target;

a receiver configured to receive, at plural sample time intervals, radar signals due to reflection or interaction of the transmitted plural UWB pulses from the target; and

a processor configured to:

form plural channel impulse response profiles, across subsets of the plural sample time intervals, from the received radar signals;

identify, in each of the plural channel impulse response profiles, one sample time interval of the plural sample time intervals as a target sample time interval in which the received radar signals are due to reflection from the target;

evaluate radar signals of interest in the target sample time interval, each of the radar signals of interest defined as respective magnitude and phase of the plural channel impulse response profiles in the target sample time interval, in order to determine for a phase of a target contribution of one or more of the radar signals of interest to a total radar signal of interest comprising the radar signals of interest; and

to determine at least one of a location or movement information of the target based on the phase of the target contribution.

16 . The arrangement according to claim 15 , wherein each of the radar signals of interest comprises:

a crosstalk contribution, being a contribution due to back coupling or crosstalk between the transmitter, transmitting the plural UWB radar radiation pulses, and the receiver, receiving the radar signals; and

the target contribution, being a contribution due to interaction or reflection of the transmitted plural UWB radar radiation pulses at the target.

17 . The arrangement according to claim 16 , wherein the crosstalk contribution is determined by averaging the radar signals of interest over an averaging time range to generate an approximate crosstalk contribution, and wherein the approximate crosstalk contribution is subtracted from the radar signals of interest within the averaging time range, in order to derive approximate target contributions within the averaging time range, each approximate target contribution comprising at least an approximate target phase and an approximate target magnitude.

18 . The arrangement according to claim 16 , wherein the processor is further configured to:

determine the crosstalk contribution by processing the radar signals of interest; and

subtract the crosstalk contribution from each of the radar signals of interest, in order to derive the target contributions, each target contribution comprising at least a target phase and a target magnitude.

19 . The arrangement according to claim 16 , wherein the processor is further configured to:

form cumulative phases of the approximate target phases over different cumulative phase time ranges; and

determine a cumulative phase time range of interest, where the cumulative phase of the approximate target phases satisfies a criterium.