r = beat2range(fb,slope) converts
the beat frequency of
a dechirped linear FMCW signal to its corresponding range. slope is
the slope of the FMCW sweep.

r = beat2range(fb,slope,c) specifies
the signal propagation speed.

Beat frequency of dechirped signal, specified as an M-by-1 vector
or M-by-2 matrix in hertz. If the FMCW signal performs an upsweep
or downsweep, fb is a vector of beat frequencies.

If the FMCW signal has a triangular sweep, fb is
an M-by-2 matrix in which each row represents a pair of beat frequencies.
Each row has the form [UpSweepBeatFrequency,DownSweepBeatFrequency].

Slope of FMCW sweep, specified as a nonzero scalar in hertz
per second. If the FMCW signal has a triangular sweep, slope is
the sweep slope of the up-sweep half. In this case, slope must
be positive and the down-sweep half is assumed to have a slope of -slope.

For an upsweep or downsweep FMCW signal, the
beat frequency is F_{t} – F_{r}.
In this expression, F_{t} is
the transmitted signal's carrier frequency, and F_{r} is
the received signal's carrier frequency.

For an FMCW signal with triangular sweep, the upsweep and downsweep
have separate beat frequencies.

If fb is a vector, the function computes c*fb/(2*slope).

If fb is an M-by-2 matrix with a row [UpSweepBeatFrequency,DownSweepBeatFrequency],
the corresponding row in r is c*((UpSweepBeatFrequency
- DownSweepBeatFrequency)/2)/(2*slope).

References

[1] Pace, Phillip. Detecting and Classifying Low
Probability of Intercept Radar. Artech House, Boston,
2009.

[2] Skolnik, M.I. Introduction
to Radar Systems. New York: McGraw-Hill, 1980.