Noise suppression and orthogonal waveform generation using phase division in a FMCW MIMO radar system

Abstract

A local oscillator phase noise-suppressed frequency modulated continuous wave (FMCW) radar includes a synthesizer having a ramp generator and an RF (radio frequency)signal generator, a frequency offset signal generator, an up-converting mixer, a power amplifier, a receiving antenna receives a receive signal reflected from an object illuminated by the transmitted signal and provides an output signal to a low noise amplifier, which generates an amplified received signal that is provided to a down-converting mixer. The down-converting mixer mixes the amplified received signal with the chirped local oscillator signal and generates an intermediate frequency (IF) signal, which is filtered by an intermediate frequency (IF) filter. The IF filter generates a filtered IF signal which is provided to an analog-to-digital converter, which generates a digitized signal that is provided to a radar signal processor for processing to obtain target range and velocity information. The radar signal processor compensates for time delays in the received signal caused by the fixed frequency offset signal mixed with the chirped local oscillator signal.

Description

[0001] NOISE SUPPRESSION AND ORTHOGONAL WAVEFORM GENERATION USING PHASE DIVISION IN A FMCW MIMO RADAR SYSTEM

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application is related to U.S. Provisional Application Serial No. 63 / 605,116, filed on December 1, 2023, and titled “LO Phase Noise Suppression And Orthogonal Waveform Generation Using Phase Division In A Frequency Modulated Continuous Wave Multiple Input Multiple Output Radar System”, the disclosure of which is incorporated herein by reference and on which priority is hereby claimed.

[0004] BACKGROUND OF THE INVENTION

[0005] Field of the Invention

[0006] The present invention generally relates to radar systems, and more particularly relates to FMCW (Frequency Modulated Continuous Wave) radar systems for automotive and other commercial and military applications, including drone navigation.

[0007] Description of the Related Art

[0008] An FMCW homodyne radar is simple in its architecture and is virtually ubiquitous in short range (up to several kilometers) radars. A typical FMCW homodyne radar 2 is shown in Figure 1 of the drawings. The FMCW homodyne radar 2 includes, as its basic components, a synthesizer 4 composed of a ramp generator 6 and an RF (radio frequency) signal generator 8 operatively coupled to the ramp generator 6. The RF signal generator 8 generates a continuous wave (CW) RF signal which is frequency modulated by the ramp generator 6. The modulated RF signal is provided to the input of a power amplifier 10, whose output is connected to a transmitting antenna 12. The typical FMCW homodyne radar 2 receives on its receiving antenna 14 a return signal reflected by an object illuminated by the transmitted signal. The receiving antenna 14 is connected to the input of a low noise amplifier 16, whose output is provided to a downconverting mixer 18. The modulated RF signal from the synthesizer 4 is also provided to the down-converting mixer 18 in the receiver leg of the FMCW radar 2. The output of the mixer 18 is essentially an IF (intermediate frequency) signal commonly referred to a beat frequency which is provided to the input of a low pass filter 20, whose output is provided to the digital backend of the homodyne radar 2, which includes an analog-to-digital (A / D) converter 22 and a radar signal processor 24 operatively coupled to the output of the A / D converter 22.

[0009] Such FMCW homodyne radars 2 are used extensively in automotive applications, among many others. This architecture exhibits none of the shortcomings of pulsed radars, among them range ambiguities, limited unambiguous Doppler space, blind range limitations, eclipsing loss and poor utilization of transmitter peak power. The FMCW radar transmitter is a constant envelope system and is capable of achieving an average-to-peak power ratio equal to 1, whereas a pulsed radar achieves an average-to-peak power ratio of typically 0.15.

[0010] However, there are limitations in the use of FMCW homodyne radars 2. Such limitations include poor transmit / receive isolation, which is typically less than 60 dB, which impacts the detection range of the FMCW homodyne radar 2. Furthermore, detection sensitivity of an FMCW homodyne radar 2 is degraded due to 1 / f noise generated in the mixer 18 and in the IF path of the receiver, as well as phase noise generated by the local oscillator (LO), in this case, the RF signal generator 8 of the synthesizer 4.

[0011] As shown in Figure 2 of the drawings, with homodyne detection, the synthesizer phase noise is at its maximum amplitude at the LO center frequency fo. No local oscillator is ideal, and jitter in the time domain translates to phase noise in the frequency domain. Poor phase noise in the synthesizer 4 results in degraded micro-Doppler characterization of radar targets and degraded (signal and interference) / noise ratio (SINR).

[0012] OBJECTS AND SUMMARY OF THE INVENTION

[0013] It is an object of the present invention to provide a radar architecture which helps suppress LO phase noise in an FMCW radar. It is another object of the present invention to provide an FMCW MIMO (Multiple Input, Multiple Output) radar having suppressed local oscillator (LO) phase noise.

[0014] It is a further object of the present invention to provide an improved FMCW radar which overcomes the inherent disadvantages of conventional FMCW radars with respect to limited radar detection range and degraded sensitivity caused by local oscillator (LO) phase noise.

[0015] It is another object of the present invention to provide a drastically simplified method of generating phase-coded orthogonal waveforms such as those required for MIMO waveform generation in which coding is applied to the low frequency oscillator waveform and not, as is customarily done, the ramp (waveform) generator.

[0016] It is still another object of the present invention to provide a method for suppressing LO phase noise in an FMCW radar.

[0017] In one form of the present invention, a conventional FMCW radar having a homodyne architecture is essentially converted to a heterodyne architecture by including a first, up- converting mixer in the transmitter leg that is fed with the chirped local oscillator (LO) signal (i.e., a modulated RF CW signal) generated by the synthesizer and a known, fixed frequency offset (Af) signal outputted by a frequency offset signal generator operatively coupled thereto. The output of the up-converting mixer is provided to the input of a power amplifier, whose output is connected to a transmitting antenna.

[0018] The return signal, reflected from an object detected by the radar, is received by a receiving antenna, whose output is connected to the input of a low noise amplifier. The output of the low noise amplifier is provided to a second, down-converting mixer in the receiver leg of the radar, which down-converting mixer is also provided with the chirped LO signal (i.e., the modulated RF CW signal) generated by the synthesizer. The output of the down-converting mixer is provided to the input of an IF (intermediate frequency) filter, whose output is provided to the digital back end of the receiver and, in particular, the input of an analog-to-digital converter, whose output is provided to a radar signal processor (RSP).

[0019] The frequency offset (Af) signal that is mixed with the chirped LO signal and transmitted introduces a calculable time delay (At) in the processed target return signal after processing by the RSP equal to (Af / BW) x T, where T equals the “chirp” time period in the LO signal and BW refers to the frequency excursion of the chirp. Since the frequency offset (Af) is known, the resultant time delay (At), being determinable, may be compensated for in the RSP.

[0020] These and other objects, features and advantages of the present invention will be apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings.

[0021] BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a block diagram of the architecture of a conventional FMCW radar shown in simplified form.

[0023] Figure 2 is a graph illustrating the frequency spectrum versus amplitude of the phase noise associated with a local oscillator of a conventional FMCW radar, generating a continuous wave (CW) signal centered at fo, and further illustrating a known and fixed frequency offset (Af) signal superimposed on the graph and mixed with the local oscillator signal in accordance with the present invention.

[0024] Figure 3 is a block diagram of the architecture of one form of an FMCW radar constructed in accordance with the present invention.

[0025] Figure 4 is a graph of frequency versus time depicting the received (reflected) signal and the transmitted signal superimposed thereon generated by an FMCW radar formed in accordance with the present invention, such as shown in Figure 3, and illustrating the time delay resulting from the known and fixed frequency offset Af.

[0026] Figure 5 is a graph of phase noise in dBc / Hz versus frequency and depicting the reduction in phase noise for an FMCW radar constructed in accordance with the present invention, such as shown in Figure 3 of the drawings, and having a frequency offset Af of 2 MHz.

[0027] Figure 6 is a block diagram of the architecture of another form of an FMCW radar constructed in accordance with the present invention. Figure 7 is a block diagram of the architecture of an FMCW MIMO (Multiple Input, Multiple Output) radar constructed in accordance with the present invention.

[0028] Figure 8 is a vector diagram of the four orthogonal phase states of the frequency offset Af of the four section FMCW MIMO radar architecture of the present invention shown in Figure 7.

[0029] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] In accordance with one form of the present invention, the architecture of an FMCW homodyne radar 2, such as depicted in Figure 1 of the drawings, is essentially converted to the architecture of an FMCW heterodyne radar 26, as shown in a simplified form in Figure 3 of the drawings. More specifically, the transmitter leg of the FMCW heterodyne radar 26 includes a synthesizer 28, such as described previously with respect to the homodyne radar architecture shown in Figure 1. The synthesizer 28 basically includes an RF signal generator 30 which generates a continuous wave (CW) signal, and a ramp generator 32 which is used to modulate preferably by a triangular or sawtooth waveform signal the CW signal generated by the RF signal generator 30 to which the output of the ramp generator 32 is electronically coupled. More specifically, the RF signal generator 30 generates a chirped LO (local oscillator) signal whose amplitude is substantially constant but whose frequency is modulated by the signal from the ramp generator 32. The modulated (chirped) LO signal from the RF signal generator 30 of the synthesizer 28 is provided to a first input of a first, up-converting mixer 34 in the transmitter leg of the FMCW radar 26 of the present invention. The radar 26 further includes a frequency offset signal generator 36 electronically coupled to a second input of the up-converting mixer 34. This signal generator 36 generates and provides to the up-converting mixer 34 a known and fixed frequency offset (Af) signal which may be, for example, 2 MHz. This fixed frequency offset (Af) signal is mixed with the chirped LO signal from the synthesizer 28 in the up-converting mixer 34 of the transmitter leg. The output of the up-converting mixer 34 is connected to the input of a power amplifier 38, whose output is connected to a transmitting antenna 40 of the radar 26. Thus, the transmitting antenna 40 transmits a chirped, or modulated, continuous wave (CW) signal embodying the frequency offset (Af).

[0031] The receiver leg of the FMCW radar 26 of the present invention includes a receiving antenna 42. The receiving antenna 42 receives the return signal of the transmitted signal that is reflected from an object detected by the radar 26. The output of the receiving antenna 42 is provided to the input of a low noise amplifier 44, whose output is provided to a first input of a down-converting mixer 46, this down-converting mixer 46 being in the receiver leg of the FMCW radar 26 of the present invention. Also provided to the down-converting mixer 46 on a second input thereof is the chirped LO signal generated by the synthesizer 28 of the radar 26 so that the down-converting mixer 46 generates on its output an IF (intermediate frequency) beat signal. The IF signal is provided to the input of an IF (e.g., low pass) filter 48, whose output is provided to the digital back end of the radar 26. More specifically, the output of the IF filter 48 is provided to the input of an analog-to-digital (A / D) converter 50 forming part of the digital back end of the radar 26, the output of the A / D converter 50 being operatively coupled to a radar signal processor (RSP) 52 also forming part of the radar digital back end. It should be noted that, in the heterodyne architecture used in each of the embodiments of the present invention disclosed herein, the preferred IF filter 48 is a bandpass filter having a low frequency cutoff equal to Af- max (fb') and a high frequency cutoff of Af. This ensures rejection of 1 / f noise generated in the down-converting mixer 46 and in an IF amplifier if such is included.

[0032] By introducing a known and fixed frequency offset Af signal to the up-converting mixer 34 in the transmitter leg of the radar 26, the chirped local oscillator signal frequency is essentially shifted away from the center frequency at fo, where the phase noise generated by the local oscillator is at its peak (i.e., is highest in amplitude), to a location on the LO frequency spectrum residing at a skirt of the phase noise spectrum where the phase noise is lower in amplitude, as notionally depicted in Figure 2 by the frequency fo + Af.

[0033] The fixed frequency offset Af introduces a time delay At in the processed target return after processing, equal to, (Af / BW) x T. Since the fixed frequency offset Af is known, the time delay in the received signal attributable to the frequency offset Af is also fixed and may be determined and, accordingly, may be compensated for in the RSP 52 of the radar 26.

[0034] Since mixing the chirped LO signal with the fixed frequency offset (Af) signal will produce upper and lower sideband signals, that is, fo + Af and fo - Af, the up-converting mixer 34 as well as the down-converting mixer 46 should be single sideband (SSB) mixers to suppress the unwanted sideband signal. The up-converting mixer 34 preferably suppresses the lower sideband frequency signal fo - Af. It is preferred if the SSB mixers 34, 46 have an unwanted sideband rejection of 40 dB, in accordance with TBR 23 of the European Telecommunications Standards Institute (ETSI).

[0035] Reference should now be had to Figure 4 of the drawings, which is a graph of frequency versus time of the received signal of the FMCW radar 26 of the present invention whose architecture is shown in Figure 3 of the drawings, and with the transmitted signal superimposed thereon. In Figure 4, the reference designation fo represents the Doppler shift of the received signal reflected from a moving target. The “chirp” T duration in the example shown in Figure 4 is approximately 16 microseconds, and the bandwidth (BW) or excursion is 200 MHz in an example embodiment.

[0036] Figure 4 illustrates the frequency as a function of time for the signal output of the RF signal generator 30, using the dashed line. This signal is the local oscillator signal for embodiment and operates with a baseline frequency of fQ. The signal includes a frequency ramp in which the LO frequency increases from f0to f0+ BW. The up-conversion mixer 34 is used to produce a transmitted signal waveform that has frequencies that ramp from f0+ A to f0+ A + BW, as illustrated with the solid thick lined signal. Two reflected signal waveforms are illustrated in the figure, corresponding to signals that would be received by antenna 42. The signal illustrated as a thin line shows the frequency as a function of time for a reflected signal from a moving target. This signal is delayed by a time Atfi= — relative to the transmitted signal, corresponding to the round-trip delay time to a target a distance R away from the sensor (i.e., the receiving antenna 42), and where “c” equals the speed of light (approximately 3 x 108meters / sec). The signal is also shown with a frequency reduction of fDrelative to the transmitted signa that results from the target velocity moving away from the sensor (i.e., the receiving antenna 42). A signal corresponding to a stationary target, shown with the dotted line, indicates the received target signal that would be received by antenna 42 from a stationary target. This received signal still has the delay Atfirelative to the transmitted signal, but has no Doppler shift.

[0037] In general, the term fbis used herein to indicate the frequency difference between the transmitted signal and signals reflected from a target. The parameters fbmand fbsare the difference frequencies between the transmitted and received frequencies from a moving target and stationary target, respectively. A homodyne system would measure fbmand fbs, but the heterodyne embodiments of this invention measure the difference frequencies with the local oscillator, which are given by A — fbmand A — fbsfor the moving target and stationary targets, respectively. When the IF signal is processed by the RSP 52 , the measured frequency of the IF signal, fIF, can be converted to a time delay through where this time delay is related to the target range through with At being an apparent time delay related to chirp parameters and the frequency offset and the target range resulting in a reduction of the time delay, in one embodiment of the invention.

[0038] For example, and in accordance with a method of the present invention, the frequency offset Af added in the transmitter leg of the FMCW radar 26 of the present invention generates a result in time delay, At, after Fourier processing, that is equal to (Af / 200) xl6 microseconds, that is, At = 160 nanoseconds, for a “chirp” of 16 microseconds, a frequency offset (Af) of 2 MHz and a BW of 200 MHz. The time delay, At, is calculable, since the frequency offset Af provided by the frequency offset signal generator 36 in the transmitter leg of the radar 26 is a known and fixed value. Since the time delay, At, skews the received signal in time, in that the target appears to be farther away than it actually is, it may be compensated for in the RSP 52 of the radar 26 by producing a compensating delay.

[0039] The signal waveform of Figure 4 is merely illustrative of one embodiment. Signal waveforms may include both positive and negative frequency slopes, and the use of processed data from multiple slopes may be used to extract the Doppler frequency. While the presented expressions are for the illustrated case of a positive frequency chirp, these expressions are easily adapted for the case of negative frequency chirps. Additionally, or alternatively, multiple measurements, with a single frequency slope may be used to infer both the range and velocity of a target.

[0040] One way to characterize an oscillator is in terms of its single sideband phase noise, as shown in the equation below: rfstop d’ssB=J £(f)df i start where £(f) = Noise density of power in SSB phase noise (Power-density ratio units). Units are dBc / Hz.

[0041] Thus, for a conventional FMCW homodyne radar architecture such as shown in Figure 1 of the drawings, the phase noise would be: 4>SSB=£(f)df. The frequency fbis the beat frequency resulting from the range-frequency compression process.

[0042] However, for the FMCW heterodyne radar architecture of the present invention, such as shown in Figure 3 of the drawings, in which a 2 MHz frequency offset (Af) signal is mixed with the chirped LO signal, the integrated LO phase noise would be: (f)df, that is, the integration is from A — fb(f start) to A (f stop).

[0043] The area under the curve from 0 Hz to Af can be approximated by applying a piece-wise linear fit to the actual data. A notional depiction of such is shown in Figure 5 of the drawings, where the frequency offset (Af) signal is 2 MHz.

[0044] Thus, for a 2 MHz frequency offset Af added in the transmitter leg of the FMCW radar 26 of the present invention, and for a 40 dBc / Hz magnitude sideband rejection (-60 dBc / Hz to -108 dBc / Hz), the reduction in SSB (single sideband) integrated phase noise is approximately 20 dB.

[0045] In summary, and in accordance with the present invention, the LO phase noise contribution on receive in a conventional FMCW radar architecture, such as shown in Figure 1 of the drawings, may be reduced by as much as 20 dB, or more, by introducing a small frequency offset of several MHz (in the example shown, 2 MHz). This involves modifying the conventional FMCW homodyne radar architecture to function as an FMCW heterodyne radar 26, such as shown in Figure 3 of the drawings. The small frequency offset Af introduces a known, induced range offset error which is corrected for in the radar signal processor 52. Since the LO is chirped in both the transmitter and receiver legs of the radar 26, the required, and essential, frequency / range compression functionality of a conventional FMCW radar with full duplex capability is achieved and with reduced degradation in sensitivity and range accuracy.

[0046] There are practical considerations as to the magnitude of the frequency offset (Af) signal which should be mixed with the chirped LO signal. The LO phase noise will plateau to its lowest level at some frequency deviation from the center frequency fo of the local oscillator. At that frequency, the phase noise will be sufficiently low, and one reaches the point of diminishing returns in attempting to reduce the phase noise further, since the amplitude noise of the synthesizer 28 will dominate.

[0047] The FMCW radar architectures of the present invention shown in Figures 6 and 7 should be viewed together. Figure 6 is a block diagram of the FMCW radar 26 shown in Figure 3 with a phase shifter 54 added in the transmitter leg between the frequency offset Af signal generator 36 and the IF input of the up-converting mixer 34. The phase shifter 54 adds a known phase shift to the frequency offset (Af) signal and, accordingly, to the chirped transmitted signal. This particular radar architecture, with both a known phase shift and a known frequency offset Af, is particularly useful in an FMCW MIMO (Multiple Input, Multiple Output) radar 56, an example of which is shown in Figure 7 of the drawings.

[0048] Turning now to Figure 7, the architecture of an FMCW MIMO radar 56 constructed in accordance with the present invention is shown. In this particular example, there are four FMCW radar architectures, typically referred to as radar channels but also referred to herein as radar sections, each with a transmitting antenna 40 and a receiving antenna 42, comprising the MIMO radar 56, although it is envisioned to be within the scope of the present invention to have fewer than four, or greater than four, radar channels or sections. More specifically, in the example shown in Figure 7, the architecture of the FMCW MIMO radar 56 includes a first radar section 58, a second radar section 60, a third radar section 62 and a fourth radar section 64. Each of the radar sections, the first radar section 58 through the fourth radar section 64, adds a known and different phase shift to the frequency offset (Af) signal and thus the transmitted signal of that section. Preferably, the four radar sections, or channels 58-64, transmit orthogonal waveforms so that there is zero cross-correlation among the received signals of the four radar sections 58-64 reflected by an object. Also, each radar section 58-64, rather than having a phase shifter 54 and a frequency offset signal generator 36 which generate phase shifted, frequency offset (Af) signals independently of the other radar sections or channels 58-64, has its transmitter leg connected to a common, multibit phase shifter 54a fed by a common frequency offset generator 36a, as shown in Figure 7. More specifically, the output signal from the common frequency offset generator 36a is provided to the input of the common, multibit phase shifter 54a, which generates four orthogonally phase shifted, frequency offset (Af) signals, each signal being provided on the outputs of the multibit phase shifter 54a to an input of the up-converting mixer 34 in the transmitter leg of respective radar sections 58-64. Other than the changes described above, each radar section or channel 58-64 takes on the architecture of the FMCW radar shown in Figure 6.

[0049] For example, the first radar section 58 of the FMCW radar architecture provides a 0- degree (or 360 degree) phase shift to the frequency offset (Af) signal and thus the signal transmitted by the first section 58. In this example, the first radar section 58 essentially adds no intentional phase shift to the frequency offset (Af) signal and the transmitted signal.

[0050] The second radar section 60 of the FMCW radar architecture, or any one of the other radar sections 58, 62, 64, connected to the common multibit phase shifter 54a, adds a 90 degree phase shift by the common phase shifter 54a to the frequency offset (Af) signal in its transmitter leg and thus the transmitted signal of the second radar section 60. Similarly, the third radar section 62, or any one of the other radar sections 58, 60, 64, of the FMCW MIMO radar architecture, by its connection to the common multibit phase shifter 54a, adds a 180 degree phase shift to the frequency offset (Af) signal in its transmitter leg and thus the transmitted signal of the third radar section 62. Likewise, the fourth radar section 64, or any one of the other radar sections 58-62, of the FMCW MIMO radar architecture, by its connection to the common multibit phase shifter 54a, adds a 270 degree phase shift to the frequency offset (Af) signal in its transmitter leg and thus the signal transmitted by the fourth radar section 64.

[0051] Thus, each of the signals transmitted by the first radar section 58, the second radar section 60, the third radar section 62 and the fourth radar section 64 of the FMCW MIMO radar 26 is orthogonal to any other waveform of the transmitted signals of any other radar section 58- 64 so that there will be zero cross-correlation among the four received signals of the first radar section 58 through the fourth radar section 64 reflected by an object. Each radar section 58-64 transmitting a signal having a known phase shift and an orthogonal waveform allows the radar signal processor 66 of the MIMO radar 56, which is shared and to which the four radar sections 58-64 are electronically coupled, to discriminate between the received orthogonal signals through application of matched filtering and to compensate for the time delay caused by Af and to provide accurate range and velocity information as well as direction of arrival information for, and to improve the measured bearing accuracy of, the object detected by the FMCW MIMO radar 56.

[0052] As is also shown in Figure 7, the architecture of the FMCW MIMO radar of the present invention includes a common reference clock 70 preferably operating at 40 MHz. The clock signal generated by the common reference clock 70 on its output is provided to the ramp generator 6 of the frequency synthesizer 4 of each radar section or channel 58-64 to achieve LO phase coherency. An AT-cut temperature compensated crystal oscillator (TCXO) is suitable for use as the reference clock 70.

[0053] Thus, in accordance with the method of the present invention, performing FMCW radar frequency-range compression using the implementation of the MIMO radar architecture shown by way of example in Figure 7 that relies on separate and distinct transmit and receive channels which maps differences in measured frequency to computed differences in range. By determining the frequency difference (which corresponds to a known time delay) the target range can be computed. This method of generating orthogonal waveforms, such as the MIMO waveforms generated by the radar architecture shown in Figure 7, is drastically simplified compared to standard practice. Phase coding is applied to the low frequency offset of the local oscillator waveform not, as is customarily done, to the ramp waveform provided by the ramp generator in the synthesizer. To the knowledge of the inventor, phase division coding in an FMCW MIMO radar has never been accomplished heretofore.

[0054] The phase of the frequency offset Af can assume any one of four phase states, as shown in the vector diagram of Figure 8. This arrangement can provide the phase coding for up to four MIMO channels. A phased array radar, such as the MIMO radar architecture 56 shown in Figure 7, having this capability vastly simplifies the coding and distribution of the orthogonal waveform to the multiplicity of transmit elements comprising the phased array. The frequency modulated continuous wave (FMCW) radar system 26, 56 and method of the present invention will now be further described.

[0055] In a first embodiment of the present invention, a frequency modulated continuous wave (FMCW) radar 26 has an architecture which may comprise a transmitter section and a receiver section. The transmitter section may include a synthesizer 28 having a ramp generator 32 and an RF (radio frequency) signal generator 30, the ramp generator 32 generating a ramp-like signal, the RF signal generator 30 being responsive to the ramp-like signal generated by the ramp generator 32 and generating a chirped local oscillator signal in response thereto; a frequency offset signal generator 36, the frequency offset signal generator 36 generating a frequency offset signal having a known and fixed frequency offset; an up-converting mixer 34, the up-converting mixer 34 being responsive to the chirped local oscillator signal generated by the RF signal generator 30 and being responsive to the frequency offset signal generated by the frequency offset signal generator 36 and generating an up-converted mixer signal in response to the chirped local oscillator signal and the frequency offset signal; a power amplifier 38, the power amplifier 38 being responsive to the up-converted mixer signal generated by the up-converting mixer 34 and generating an amplified signal in response thereto; and a transmitting antenna 40, the transmitting antenna 40 being responsive to the amplified signal generated by the power amplifier 38 and transmitting a transmit signal in response thereto.

[0056] In the first embodiment, the receiver section may include a receiving antenna 42, the receiving antenna 42 receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a low noise amplifier 44, the low noise amplifier 44 being responsive to the receive antenna output signal generated by the receiving antenna 42 and generating an amplified received signal in response thereto; a down-converting mixer 46, the down-converting mixer 46 being responsive to the amplified received signal generated by the low noise amplifier 44 and being responsive to the chirped local oscillator signal generated by the RF signal generator 30 and generating an intermediate frequency (IF) signal (also referred to as a beat frequency) in response to the amplified received signal and the chirped local oscillator signal; an intermediate frequency (IF) filter 48, the intermediate frequency (IF) filter 48 being responsive to the intermediate frequency (IF) signal generated by the down-converting mixer 46 and generating a filtered intermediate frequency (IF) signal in response thereto; an analog-to-digital converter 50, the analog-to-digital converter 50 being responsive to the filtered intermediate frequency (IF) signal generated by the intermediate frequency (IF) filter 48 and generating a digitized filtered intermediate frequency (IF) signal in response thereto; and a radar signal processor 52, the radar signal processor 52 being responsive to the digitized filtered intermediate frequency (IF) signal generated by the analog-to-digital converter 50 and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of the radar.

[0057] In the first embodiment, the chirped local oscillator signal generated by the RF signal generator 30 of the synthesizer 28 of the transmitter section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which may include a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0058] In the first embodiment, the frequency offset signal generated by the frequency offset signal generator 36, when mixed by the up-converting mixer 34 with the chirped local oscillator signal generated by the RF signal generator 30, causes the up-converted mixer signal to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0059] In the first embodiment, the frequency offset signal generated by the frequency offset signal generator 36 introduces a time delay in the receive signal received by the receiving antenna 42, the time delay being compensated for in the radar signal processor 52.

[0060] In a second embodiment of the present invention, a frequency modulated continuous wave (FMCW) radar 26 has an architecture which may comprise a transmitter section and a receiver section. The transmitter section may include a synthesizer 28 having a ramp generator 32 and an RF (radio frequency) signal generator 30, the ramp generator 32 generating a ramplike signal, the RF signal generator 30 being responsive to the ramp-like signal generated by the ramp generator 32 and generating a chirped local oscillator signal in response thereto; a frequency offset signal generator 36, the frequency offset signal generator 36 generating a frequency offset signal having a known and fixed frequency offset; a phase shifter 54, the phase shifter 54 being responsive to the frequency offset signal generated by the frequency offset signal generator 36 and generating a phase-shifted frequency offset signal in response thereto, the phase-shifted frequency offset signal corresponding to the frequency offset signal shifted in phase by a predetermined phase shift; an up-converting mixer 34, the up-converting mixer 34 being responsive to the chirped local oscillator signal generated by the RF signal generator 30 and being responsive to the phase-shifted frequency offset signal generated by the phase shifter 54 and generating an up-converted mixer signal in response to the chirped local oscillator signal and the phase-shifted frequency offset signal; a power amplifier 38, the power amplifier 38 being responsive to the up-converted mixer signal generated by the up-converting mixer 34 and generating an amplified signal in response thereto; and a transmitting antenna 40, the transmitting antenna 40 being responsive to the amplified signal generated by the power amplifier 38 and transmitting a transmit signal in response thereto.

[0061] In the second embodiment, the receiver section may include a receiving antenna 42, the receiving antenna 42 receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a low noise amplifier 44, the low noise amplifier 44 being responsive to the receive antenna output signal generated by the receiving antenna 42 and generating an amplified received signal in response thereto; a down-converting mixer 46, the down-converting mixer 46 being responsive to the amplified received signal generated by the low noise amplifier 44 and being responsive to the chirped local oscillator signal generated by the RF signal generator 30 and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; an intermediate frequency (IF) filter 48, the intermediate frequency (IF) filter 48 being responsive to the intermediate frequency (IF) signal generated by the downconverting mixer 46 and generating a filtered intermediate frequency (IF) signal in response thereto; an analog-to-digital converter 50, the analog-to-digital converter 50 being responsive to the filtered intermediate frequency (IF) signal generated by the intermediate frequency (IF) filter 48 and generating a digitized filtered intermediate frequency (IF) signal in response thereto; and a radar signal processor 52, the radar signal processor 52 being responsive to the digitized filtered intermediate frequency (IF) signal generated by the analog-to-digital converter 50 and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of the radar.

[0062] In the second embodiment, the chirped local oscillator signal generated by the RF signal generator 30 of the synthesizer 28 of the transmitter section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which may include a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0063] In the second embodiment, the phase-shifted frequency offset signal generated by the phase shifter 54, when mixed by the up-converting mixer 34 with the chirped local oscillator signal generated by the RF signal generator 30, causes the up-converted mixer signal to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0064] In the second embodiment, the frequency offset signal generated by the frequency offset signal generator 36 introduces a time delay in the receive signal received by the receiving antenna 42, the time delay being compensated for in the radar signal processor 52.

[0065] In the second embodiment, the phase-shifted frequency offset signal generated by the phase shifter 54 introduces a corresponding phase shift in the receive signal received by the receiving antenna 42 substantially equal to the predetermined phase shift caused by the phase shifter 54, the phase shift in the receive signal being compensated for in the radar signal processor 52.

[0066] In a third embodiment of the present invention, a frequency modulated continuous wave (FMCW) multiple input, multiple output (MIMO) radar 56 has an architecture which may comprise a common frequency offset signal generator 36a, the common frequency offset signal generator 36a generating a frequency offset signal having a known and fixed frequency offset; a common multibit phase shifter 54a, the common multibit phase shifter 54a having a first output and at least a second output, the common multibit phase shifter 54a being responsive to the frequency offset signal generated by the common frequency offset signal generator 36a and generating a first phase-shifted frequency offset signal on the first output thereof and at least a second phase-shifted frequency offset signal on the at least second output thereof, the first phase- shifted frequency offset signal having a first phase shift, the at least second phase-shifted frequency offset signal having a second phase shift, the first phase shift being orthogonal to the second phase shift; a common reference clock 70, the common reference clock 70 generating a clock signal; and a first radar section 58 and at least a second radar section 60. In the third embodiment, the first radar section 58 may include a first transmitter section and a first receiver section. The first transmitter section of the first radar section 58 may include a first synthesizer 28a having a first ramp generator 32a and a first RF (radio frequency) signal generator 30a, the first ramp generator 32a generating a ramp-like signal, the clock signal generated by the common reference clock 70 being provided to the first ramp generator 32a, the first RF signal generator 30a being responsive to the ramp-like signal generated by the first ramp generator 32a and generating a chirped local oscillator signal in response thereto; a first up- converting mixer 34a, the first up-converting mixer 34a being responsive to the chirped local oscillator signal generated by the first RF signal generator 30a and being responsive to the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and generating an up-converted mixer signal in response to the chirped local oscillator signal and the first phase-shifted frequency offset signal; a first power amplifier 38a, the first power amplifier 38a being responsive to the up-converted mixer signal generated by the first up-converting mixer 34a and generating an amplified signal in response thereto; and a first transmitting antenna 40a, the first transmitting antenna 40a being responsive to the amplified signal generated by the first power amplifier 38a and transmitting a transmit signal in response thereto.

[0067] In the third embodiment, the receiver section of the first radar section 58 may include a first receiving antenna 42a, the first receiving antenna 42a receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a first low noise amplifier 44a, the first low noise amplifier 44a being responsive to the receive antenna output signal generated by the first receiving antenna 42a and generating an amplified received signal in response thereto; a first down-converting mixer 46a, the first down-converting mixer 46a being responsive to the amplified received signal generated by the first low noise amplifier 44a and being responsive to the chirped local oscillator signal generated by the first RF signal generator 30a and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a first intermediate frequency (IF) filter 48a, the first intermediate frequency (IF) filter 48a being responsive to the intermediate frequency (IF) signal generated by the first down-converting mixer 46a and generating a filtered intermediate frequency (IF) signal in response thereto; and a first analog-to-digital converter 50a, the first analog-to-digital converter 50a being responsive to the filtered intermediate frequency (IF) signal generated by the first intermediate frequency (IF) filter 48a and generating a digitized filtered intermediate frequency (IF) signal in response thereto.

[0068] In the third embodiment, the at least second radar section 60 may include a second transmitter section and a second receiver section. The second transmitter section of the at least second radar section 60 may include a second synthesizer 28b having a second ramp generator 32b and a second RF (radio frequency) signal generator 30b, the second ramp generator 32b generating a ramp-like signal, the clock signal generated by the common reference clock 70 being provided to the second ramp generator 32b, the second RF signal generator 30b being responsive to the ramp-like signal generated by the second ramp generator 32b and generating a chirped local oscillator signal in response thereto; a second up-converting mixer 34b, the second up-converting mixer 34b being responsive to the chirped local oscillator signal generated by the second RF signal generator 30b and being responsive to the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and generating an up-converted mixer signal in response to the chirped local oscillator signal and the second phase-shifted frequency offset signal; a second power amplifier 38b, the second power amplifier 38b being responsive to the up-converted mixer signal generated by the second up-converting mixer 34b and generating an amplified signal in response thereto; and a second transmitting antenna 40b, the second transmitting antenna 40b being responsive to the amplified signal generated by the second power amplifier 38b and transmitting a transmit signal in response thereto.

[0069] In the third embodiment, the receiver section of the at least second radar section 60 may include a second receiving antenna 42b, the second receiving antenna 42b receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a second low noise amplifier 44b, the second low noise amplifier 44b being responsive to the receive antenna output signal generated by the second receiving antenna 42b and generating an amplified received signal in response thereto; a second down-converting mixer 46b, the second down-converting mixer 46b being responsive to the amplified received signal generated by the second low noise amplifier 44b and being responsive to the chirped local oscillator signal generated by the second RF signal generator 30b and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a second intermediate frequency (IF) filter 48b, the second intermediate frequency (IF) filter 48b being responsive to the intermediate frequency (IF) signal generated by the second down-converting mixer 46b and generating a filtered intermediate frequency (IF) signal in response thereto; and a second analog-to-digital converter 50b, the second analog-to-digital converter 50b being responsive to the filtered intermediate frequency (IF) signal generated by the second intermediate frequency (IF) filter 48b and generating a digitized filtered intermediate frequency (IF) signal in response thereto.

[0070] In the third embodiment, the architecture of the FMCW MIMO radar 56 further may include a radar signal processor 66, the radar signal processor 66 being responsive to the digitized filtered intermediate frequency (IF) signal generated by the first analog-to-digital converter 50a of the first radar section 58 and the digitized filtered intermediate frequency (IF) signal generated by the second analog-to-digital converter 50b of the at least second radar section 60 and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of at least one of the first radar section 58 and the at least second radar section 60.

[0071] In the third embodiment, the chirped local oscillator signal generated by the first RF signal generator 30a of the first synthesizer 28a of the first transmitter section of the first radar section 58 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which may include a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0072] In the third embodiment, the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the first radar section 58, when mixed by the first up-converting mixer 34a of the first radar section 58 with the chirped local oscillator signal generated by the first RF signal generator 30a of the first radar section 58, causes the up- converted mixer signal generated by the first up-converting mixer 34a to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0073] In the third embodiment, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a time delay in the receive signal received by the first receiving antenna 42a of the first radar section 58, the time delay being compensated for in the radar signal processor 66. In the third embodiment, the first phase shift of the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the first radar section 58 introduces a corresponding phase shift in the receive signal received by the first receiving antenna 42a of the first radar section 58 substantially equal (for lossless reflective objects) to the predetermined first phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0074] In the third embodiment, the chirped local oscillator signal generated by the second RF signal generator 30b of the second synthesizer 28b of the second transmitter section of the at least second radar section 60 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which may include a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0075] In the third embodiment, the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the at least second radar section 60, when mixed by the second up-converting mixer 34b of the at least second radar section 60 with the chirped local oscillator signal generated by the second RF signal generator 30b of the at least second radar section 60, causes the up-converted mixer signal generated by the second up- converting mixer 34b to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0076] In the third embodiment, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a time delay in the receive signal received by the second receiving antenna 42b of the at least second radar section 60, the time delay being compensated for in the radar signal processor 66.

[0077] In the third embodiment, the second phase shift of the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the at least second radar section 60 introduces a corresponding phase shift in the receive signal received by the second receiving antenna 42b of the at least second radar section 60 substantially equal (for lossless reflective objects) to the predetermined second phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0078] In the third embodiment, the first phase shift of the first phase-shifted frequency offset signal, being orthogonal to the second phase shift of the second phase-shifted frequency offset signal, minimizes cross-correlation between the receive signal received by the first receiving antenna 42a of the first radar section 58 and the receive signal received by the second receiving antenna 42b of the at least second radar section 60.

[0079] In a fourth embodiment of the present invention, a frequency modulated continuous wave (FMCW) multiple input, multiple output (MIMO) radar 56 has an architecture which may comprise a common frequency offset signal generator 36a, the common frequency offset signal generator 36a generating a frequency offset signal having a known and fixed frequency offset; a common multibit phase shifter 54a, the common multibit phase shifter 54a having a first output, a second output, a third output and a fourth output, the common multibit phase shifter 54a being responsive to the frequency offset signal generated by the common frequency offset signal generator 36a and generating a first phase-shifted frequency offset signal on the first output thereof, a second phase-shifted frequency offset signal on the second output thereof, a third phase-shifted frequency offset signal on the third output thereof and a fourth phase-shifted frequency offset signal on the fourth output thereof, the first phase-shifted frequency offset signal having a first phase shift, the second phase-shifted frequency offset signal having a second phase shift, the third phase-shifted frequency offset signal having a third phase shift and the fourth phase-shifted frequency offset signal having a fourth phase shift, the first phase shift being orthogonal to the second phase shift, the second phase shift being orthogonal to the third phase shift, the third phase shift being orthogonal to the fourth phase shift; a common reference clock 70, the common reference clock 70 generating a clock signal; and a first radar section 58, a second radar section 60, a third radar section 62 and a fourth radar section 64.

[0080] In the fourth embodiment, the first radar section 58 may include a first transmitter section and a first receiver section. The first transmitter section of the first radar section 58 may include a first synthesizer 28a having a first ramp generator 32a and a first RF (radio frequency) signal generator 30a, the first ramp generator 32a generating a ramp-like signal, the clock signal generated by the common reference clock 70 being provided to the first ramp generator 32a, the first RF signal generator 30a being responsive to the ramp-like signal generated by the first ramp generator 32a and generating a chirped local oscillator signal in response thereto; a first up- converting mixer 34a, the first up-converting mixer 34a being responsive to the chirped local oscillator signal generated by the first RF signal generator 30a and being responsive to the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and generating an up-converted mixer signal in response to the chirped local oscillator signal and the first phase-shifted frequency offset signal; a first power amplifier 38a, the first power amplifier 38a being responsive to the up-converted mixer signal generated by the first up-converting mixer 34a and generating an amplified signal in response thereto; and a first transmitting antenna 40a, the first transmitting antenna 40a being responsive to the amplified signal generated by the first power amplifier 38a and transmitting a transmit signal in response thereto.

[0081] In the fourth embodiment, the receiver section of the first radar section 58 may include a first receiving antenna 42a, the first receiving antenna 42a receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a first low noise amplifier 44a, the first low noise amplifier 44a being responsive to the receive antenna output signal generated by the first receiving antenna 42a and generating an amplified received signal in response thereto; a first down-converting mixer 46a, the first down-converting mixer 46a being responsive to the amplified received signal generated by the first low noise amplifier 44a and being responsive to the chirped local oscillator signal generated by the first RF signal generator 30a and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a first intermediate frequency (IF) filter 48a, the first intermediate frequency (IF) filter 48a being responsive to the intermediate frequency (IF) signal generated by the first down-converting mixer 46a and generating a filtered intermediate frequency (IF) signal in response thereto; and a first analog-to-digital converter 50a, the first analog-to-digital converter 50a being responsive to the filtered intermediate frequency (IF) signal generated by the first intermediate frequency (IF) filter 48a and generating a digitized filtered intermediate frequency (IF) signal in response thereto.

[0082] In the fourth embodiment, the second radar section 60 may include a second transmitter section and a second receiver section. The second transmitter section of the second radar section 60 may include a second synthesizer 28b having a second ramp generator 32b and a second RF (radio frequency) signal generator 30b, the second ramp generator 32b generating a ramp-like signal, the clock signal generated by the common reference clock 70 being provided to the second ramp generator 32b, the second RF signal generator 30b being responsive to the ramplike signal generated by the second ramp generator 32b and generating a chirped local oscillator signal in response thereto; a second up-converting mixer 34b, the second up-converting mixer 34b being responsive to the chirped local oscillator signal generated by the second RF signal generator 30b and being responsive to the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and generating an up-converted mixer signal in response to the chirped local oscillator signal and the second phase-shifted frequency offset signal; a second power amplifier 38b, the second power amplifier 38b being responsive to the up-converted mixer signal generated by the second up-converting mixer 34b and generating an amplified signal in response thereto; and a second transmitting antenna 40b, the second transmitting antenna 40b being responsive to the amplified signal generated by the second power amplifier 38b and transmitting a transmit signal in response thereto.

[0083] In the fourth embodiment, the receiver section of the second radar section 60 may include a second receiving antenna 42b, the second receiving antenna 42b receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a second low noise amplifier 44b, the second low noise amplifier 44b being responsive to the receive antenna output signal generated by the second receiving antenna 42b and generating an amplified received signal in response thereto; a second down-converting mixer 46b, the second down-converting mixer 46b being responsive to the amplified received signal generated by the second low noise amplifier 44b and being responsive to the chirped local oscillator signal generated by the second RF signal generator 30b and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a second intermediate frequency (IF) filter 48b, the second intermediate frequency (IF) filter 48b being responsive to the intermediate frequency (IF) signal generated by the second down-converting mixer 46b and generating a filtered intermediate frequency (IF) signal in response thereto; and a second analog-to-digital converter 50b, the second analog-to-digital converter 50b being responsive to the filtered intermediate frequency (IF) signal generated by the second intermediate frequency (IF) filter 48b and generating a digitized filtered intermediate frequency (IF) signal in response thereto. In the fourth embodiment, the third radar section 62 may include a third transmitter section and a third receiver section. The third transmitter section of the third radar section 62 may include a third synthesizer 28c having a third ramp generator 32c and a third RF (radio frequency) signal generator 30c, the third ramp generator 32c generating a ramp-like signal, the clock signal generated by the common reference clock 70 being provided to the third ramp generator 32c, the third RF signal generator 30c being responsive to the ramp-like signal generated by the third ramp generator 32c and generating a chirped local oscillator signal in response thereto; a third up-converting mixer 34c, the third up-converting mixer 34c being responsive to the chirped local oscillator signal generated by the third RF signal generator 30c and being responsive to the third phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and generating an up-converted mixer signal in response to the chirped local oscillator signal and the third phase-shifted frequency offset signal; a third power amplifier 38c, the third power amplifier 38c being responsive to the up-converted mixer signal generated by the third up-converting mixer 34c and generating an amplified signal in response thereto; and a third transmitting antenna 40c, the third transmitting antenna 40c being responsive to the amplified signal generated by the third power amplifier 38c and transmitting a transmit signal in response thereto.

[0084] In the fourth embodiment, the receiver section of the third radar section 62 may include a third receiving antenna 42c, the third receiving antenna 42c receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a third low noise amplifier 44c, the third low noise amplifier 44c being responsive to the receive antenna output signal generated by the third receiving antenna 42c and generating an amplified received signal in response thereto; a third down-converting mixer 46c, the third down-converting mixer 46c being responsive to the amplified received signal generated by the third low noise amplifier 44c and being responsive to the chirped local oscillator signal generated by the third RF signal generator 30c and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a third intermediate frequency (IF) filter 48c, the third intermediate frequency (IF) filter 48c being responsive to the intermediate frequency (IF) signal generated by the third down-converting mixer 46c and generating a filtered intermediate frequency (IF) signal in response thereto; and a third analog-to-digital converter 50c, the third analog-to-digital converter 50c being responsive to the filtered intermediate frequency (IF) signal generated by the third intermediate frequency (IF) filter 48c and generating a digitized filtered intermediate frequency (IF) signal in response thereto.

[0085] In the fourth embodiment, the fourth radar section 64 may include a fourth transmitter section and a fourth receiver section. The fourth transmitter section of the fourth radar section 64 may include a fourth synthesizer 28d having a fourth ramp generator 32d and a fourth RF (radio frequency) signal generator 30d, the fourth ramp generator 32d generating a ramp-like signal, the clock signal generated by the common reference clock 70 being provided to the fourth ramp generator 32d, the fourth RF signal generator 30d being responsive to the ramp-like signal generated by the fourth ramp generator 32d and generating a chirped local oscillator signal in response thereto; a fourth up-converting mixer 34d, the fourth up-converting mixer 34d being responsive to the chirped local oscillator signal generated by the fourth RF signal generator 30d and being responsive to the fourth phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and generating an up-converted mixer signal in response to the chirped local oscillator signal and the fourth phase-shifted frequency offset signal; a fourth power amplifier 38d, the fourth power amplifier 38d being responsive to the up-converted mixer signal generated by the fourth up-converting mixer 34d and generating an amplified signal in response thereto; and a fourth transmitting antenna 40d, the fourth transmitting antenna 40d being responsive to the amplified signal generated by the fourth power amplifier 38d and transmitting a transmit signal in response thereto.

[0086] In the fourth embodiment, the receiver section of the fourth radar section 64 may include a fourth receiving antenna 42d, the fourth receiving antenna 42d receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a fourth low noise amplifier 44d, the fourth low noise amplifier 44d being responsive to the receive antenna output signal generated by the fourth receiving antenna 42d and generating an amplified received signal in response thereto; a fourth downconverting mixer 46d, the fourth down-converting mixer 46d being responsive to the amplified received signal generated by the fourth low noise amplifier 44d and being responsive to the chirped local oscillator signal generated by the fourth RF signal generator 30d and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a fourth intermediate frequency (IF) filter 48d, the fourth intermediate frequency (IF) filter 48d being responsive to the intermediate frequency (IF) signal generated by the fourth down-converting mixer 46d and generating a filtered intermediate frequency (IF) signal in response thereto; and a fourth analog-to-digital converter 50d, the fourth analog-to- digital converter 50d being responsive to the filtered intermediate frequency (IF) signal generated by the fourth intermediate frequency (IF) filter 48d and generating a digitized filtered intermediate frequency (IF) signal in response thereto.

[0087] In the fourth embodiment, the architecture of the FMCW MIMO radar 56 further may include a radar signal processor 66, the radar signal processor 66 being responsive to the digitized filtered intermediate frequency (IF) signal generated by the first analog-to-digital converter 50a of the first radar section 58, the digitized filtered intermediate frequency (IF) signal generated by the second analog-to-digital converter 50b of the second radar section 60, the digitized filtered intermediate frequency (IF) signal generated by the third analog-to-digital converter 50c of the third radar section 62 and the digitized filtered intermediate frequency (IF) signal generated by the fourth analog-to-digital converter 50d of the fourth radar section 64 and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of at least one of the first radar section 58, the second radar section 60, the third radar section 62 and the fourth radar section 64.

[0088] In the fourth embodiment, the chirped local oscillator signal generated by the first RF signal generator 30a of the first synthesizer 28a of the first transmitter section of the first radar section 58 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which may include a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0089] In the fourth embodiment, the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the first radar section 58, when mixed by the first up-converting mixer 34a of the first radar section 58 with the chirped local oscillator signal generated by the first RF signal generator 30a of the first radar section 58, causes the up- converted mixer signal generated by the first up-converting mixer 34a to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset. In the fourth embodiment, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a known time delay in the receive signal received by the first receiving antenna 42a of the first radar section 58, the time delay being compensated for in the radar signal processor 66.

[0090] In the fourth embodiment, the first phase shift of the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the first radar section 58 introduces a corresponding phase shift in the receive signal received by the first receiving antenna 42a of the first radar section 58 substantially equal (for lossless reflective objects) to the predetermined first phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0091] In the fourth embodiment, the chirped local oscillator signal generated by the second RF signal generator 30b of the second synthesizer 28b of the second transmitter section of the second radar section 60 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which may include a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0092] In the fourth embodiment, the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the second radar section 60, when mixed by the second up-converting mixer 34b of the second radar section 60 with the chirped local oscillator signal generated by the second RF signal generator 30b of the second radar section 60, causes the up-converted mixer signal generated by the second up-converting mixer 34b to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0093] In the fourth embodiment, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a time delay in the receive signal received by the second receiving antenna 42b of the second radar section 60, the time delay being compensated for in the radar signal processor 66. In the fourth embodiment, the second phase shift of the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the second radar section 60 introduces a corresponding phase shift in the receive signal received by the second receiving antenna 42b of the second radar section 60 substantially equal (for lossless reflective objects) to the predetermined second phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0094] In the fourth embodiment, the chirped local oscillator signal generated by the third RF signal generator 30c of the third synthesizer 28c of the third transmitter section of the third radar section 62 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which may include a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0095] In the fourth embodiment, the third phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the third radar section 62, when mixed by the third up-converting mixer 34c of the third radar section 62 with the chirped local oscillator signal generated by the third RF signal generator 30c of the third radar section 62, causes the up- converted mixer signal generated by the third up-converting mixer 34c to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0096] In the fourth embodiment, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a time delay in the receive signal received by the third receiving antenna 42c of the third radar section 62, the time delay being compensated for in the radar signal processor 66.

[0097] In the fourth embodiment, the third phase shift of the third phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the third radar section 62 introduces a corresponding phase shift in the receive signal received by the third receiving antenna 42c of the third radar section 62 substantially equal (for lossless reflective objects) to the predetermined third phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0098] In the fourth embodiment, the chirped local oscillator signal generated by the fourth RF signal generator 30d of the fourth synthesizer 28d of the fourth transmitter section of the fourth radar section 64 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which may include a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0099] In the fourth embodiment, the fourth phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the fourth radar section 64, when mixed by the fourth up-converting mixer 34d of the fourth radar section 64 with the chirped local oscillator signal generated by the fourth RF signal generator 30d of the fourth radar section 64, causes the up-converted mixer signal generated by the fourth up-converting mixer 34d to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0100] In the fourth embodiment, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a time delay in the receive signal received by the fourth receiving antenna 42d of the fourth radar section 64, the time delay being compensated for in the radar signal processor 66.

[0101] In the fourth embodiment, the fourth phase shift of the fourth phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the fourth radar section 64 introduces a corresponding phase shift in the receive signal received by the fourth receiving antenna 42d of the fourth radar section 64 substantially equal (for lossless reflective objects) to the predetermined fourth phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0102] In the fourth embodiment, the first phase shift of the first phase-shifted frequency offset signal, being orthogonal to the second phase shift of the second phase-shifted frequency offset signal, the second phase shift of the second phase-shifted frequency offset signal, being orthogonal to the third phase shift of the third phase-shifted frequency offset signal, and the third phase shift of the third phase-shifted frequency offset signal, being orthogonal to the fourth phase shift of the fourth phase-shifted frequency offset signal, minimizes cross-correlation between the receive signal received by the first receiving antenna 42a of the first radar section 58, the receive signal received by the second receiving antenna 42b of the second radar section 60, the receive signal received by the third receiving antenna 42c of the third radar section 62 and the receive signal received by the fourth receiving antenna 42d of the fourth radar section 64.

[0103] A first method of the present invention of suppressing local oscillator phase noise in a frequency modulated continuous wave (FMCW) radar 26 may include the steps of generating by a ramp generator 32 a ramp-like signal; generating by an RF (radio frequency) signal generator 30 a chirped local oscillator signal in response to the ramp-like signal; generating by a frequency offset signal generator 36 a frequency offset signal having a known and fixed frequency offset; mixing by an up-converting mixer 34 the chirped local oscillator signal and the frequency offset signal and generating an up-converted mixer signal in response thereto; generating by a power amplifier 38 an amplified signal in response to the up-converted mixer signal; transmitting by a transmitting antenna 40 a transmit signal in response to the amplified signal; receiving by a receiving antenna 42 a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; generating by a low noise amplifier 44 an amplified received signal in response to the receive antenna output signal; mixing by a down-converting mixer 46 the amplified received signal and the chirped local oscillator signal and generating an intermediate frequency (IF) signal in response thereto; filtering by an intermediate frequency (IF) filter 48 the intermediate frequency (IF) signal and generating a filtered intermediate frequency (IF) signal in response thereto; digitizing by an analog-to-digital converter 50 the filtered intermediate frequency (IF) signal and generating a digitized filtered intermediate frequency (IF) signal in response thereto; and processing by a radar signal processor 52 the digitized filtered intermediate frequency (IF) signal and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of the radar.

[0104] In the first method, the chirped local oscillator signal generated by the RF signal generator 30 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which may include a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0105] In the first method, the frequency offset signal generated by the frequency offset signal generator 36, when mixed by the up-converting mixer 34 with the chirped local oscillator signal generated by the RF signal generator 30, causes the up-converted mixer signal to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0106] In the first method, the frequency offset signal generated by the frequency offset signal generator 36 introduces a time delay in the receive signal received by the receiving antenna 42, the time delay being compensated for in the radar signal processor 52.

[0107] A second method of the present invention of suppressing local oscillator phase noise in a frequency modulated continuous wave (FMCW) radar 26 may include the steps of generating by a ramp generator 32 a ramp-like signal; generating by an RF (radio frequency) signal generator 30 a chirped local oscillator signal in response to the ramp-like signal; generating by a frequency offset signal generator 36 a frequency offset signal having a known and fixed frequency offset; phase shifting by a phase shifter 54 the frequency offset signal and generating a phase-shifted frequency offset signal in response thereto, the phase-shifted frequency offset signal corresponding to the frequency offset signal shifted in phase by a predetermined phase shift; mixing by an up-converting mixer 34 the chirped local oscillator signal and the phase-shifted frequency offset signal and generating an up-converted mixer signal in response thereto; generating by a power amplifier 38 an amplified signal in response to the up-converted mixer signal; transmitting by a transmitting antenna 40 a transmit signal in response to the amplified signal; receiving by a receiving antenna 42 a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; generating by a low noise amplifier 44 an amplified received signal in response to the receive antenna output signal; mixing by a down-converting mixer 46 the amplified received signal and the chirped local oscillator signal and generating an intermediate frequency (IF) signal in response thereto; filtering by an intermediate frequency (IF) filter 48 the intermediate frequency (IF) signal and generating a filtered intermediate frequency (IF) signal in response thereto; digitizing by an analog-to-digital converter 50 the filtered intermediate frequency (IF) signal and generating a digitized filtered intermediate frequency (IF) signal in response thereto; and processing by a radar signal processor 52 the digitized filtered intermediate frequency (IF) signal and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of the radar.

[0108] In the second method, the chirped local oscillator signal generated by the RF signal generator 30 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which may include a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0109] In the second method, the phase-shifted frequency offset signal generated by the phase shifter 54, when mixed by the up-converting mixer 34 with the chirped local oscillator signal generated by the RF signal generator 30, causes the up-converted mixer signal to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0110] In the second method, the frequency offset signal generated by the frequency offset signal generator 36 introduces a time delay in the receive signal received by the receiving antenna 42, the time delay being compensated for in the radar signal processor 52.

[0111] In the second method, the phase-shifted frequency offset signal generated by the phase shifter 54 introduces a phase shift in the receive signal received by the receiving antenna 42 substantially equal to the predetermined phase shift caused by the phase shifter 54, the phase shift in the receive signal being compensated for in the radar signal processor 52.

[0112] A third method of the present invention of suppressing local oscillator phase noise in a frequency modulated continuous wave (FMCW) multiple input, multiple output (MIMO) radar 56 having an architecture which includes a first radar section 58 and at least a second radar section 60, the first radar section 58 including a first transmitter section and a first receiver section, the at least second radar section 60 including a second transmitter section and a second receiver section, may include the steps of generating by a common frequency offset signal generator 36a a frequency offset signal having a known and fixed frequency offset; generating by a common multibit phase shifter 54a a first phase-shifted frequency offset signal and at least a second phase-shifted frequency offset signal in response to the frequency offset signal generated by the common frequency offset signal generator 36a, the common multibit phase shifter 54a having a first output and at least a second output, the common multibit phase shifter 54a generating the first phase-shifted frequency offset signal on the first output thereof and the at least second phase-shifted frequency offset signal on the at least second output thereof, the first phase-shifted frequency offset signal having a first phase shift, the at least second phase-shifted frequency offset signal having a second phase shift, the first phase shift being orthogonal to the second phase shift; generating by a common reference clock 70 a clock signal; generating by a first ramp generator 32a defining a component of a first synthesizer 28a forming part of the first transmitter section of the first radar section 58 a ramp-like signal in response to the clock signal; generating by a first RF (radio frequency) signal generator 30a defining a component of the first synthesizer 28a forming part of the first transmitter section of the first radar section 58 a chirped local oscillator signal in response to the ramp-like signal generated by the first ramp generator 32a; generating by a first up-converting mixer 34a forming part of the first transmitter section of the first radar section 58 an up-converted mixer signal in response to the chirped local oscillator signal generated by the first RF signal generator 30a and in response to the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a; generating by a first power amplifier 38a forming part of the first transmitter section of the first radar section 58 an amplified signal in response to the up-converted mixer signal generated by the first up- converting mixer 34a; transmitting by a first transmitting antenna 40a forming part of the first transmitter section of the first radar section 58 a transmit signal in response to the amplified signal generated by the first power amplifier 38a; receiving by a first receiving antenna 42a forming part of the first receiver section of the first radar section 58 a receive signal reflected from an object illuminated by the transmit signal transmitted by the first transmitting antenna 40a and generating a receive antenna output signal in response thereto; generating by a first low noise amplifier 44a forming part of the first receiver section of the first radar section 58 an amplified received signal in response to the receive antenna output signal generated by the first receiving antenna 42a; generating by a first down-converting mixer 46a forming part of the first receiver section of the first radar section 58 an intermediate frequency (IF) signal in response to the amplified received signal generated by the first low noise amplifier 44a and in response to the chirped local oscillator signal generated by the first RF signal generator 30a; generating by a first intermediate frequency (IF) filter 48a forming part of the first receiver section of the first radar section 58 a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the first down-converting mixer 46a; generating by a first analog-to- digital converter 50a forming part of the first radar section 58 a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the first intermediate frequency (IF) filter 48a; generating by a second ramp generator 32b defining a component of a second synthesizer 28b forming part of the second transmitter section of the second radar section 60 a ramp-like signal in response to the clock signal; generating by a second RF (radio frequency) signal generator 30b defining a component of the second synthesizer 28b forming part of the second transmitter section of the second radar section 60 a chirped local oscillator signal in response to the ramp-like signal generated by the second ramp generator 32b; generating by a second up-converting mixer 34b forming part of the second transmitter section of the second radar section 60 an up-converted mixer signal in response to the chirped local oscillator signal generated by the second RF signal generator 30b and in response to the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a; generating by a second power amplifier 38b forming part of the second transmitter section of the second radar section 60 an amplified signal in response to the up-converted mixer signal generated by the second up-converting mixer 34b; transmitting by a second transmitting antenna 40b forming part of the second transmitter section of the second radar section 60 a transmit signal in response to the amplified signal generated by the second power amplifier 38b; receiving by a second receiving antenna 42b forming part of the second receiver section of the second radar section 60 a receive signal reflected from an object illuminated by the transmit signal transmitted by the second transmitting antenna 40b and generating a receive antenna output signal in response thereto; generating by a second low noise amplifier 44b forming part of the second receiver section of the second radar section 60 an amplified received signal in response to the receive antenna output signal generated by the second receiving antenna 42b; generating by a second down-converting mixer 46b forming part of the second receiver section of the second radar section 60 an intermediate frequency (IF) signal in response to the amplified received signal generated by the second low noise amplifier 44b and in response to the chirped local oscillator signal generated by the second RF signal generator 30b; generating by a second intermediate frequency (IF) filter 48b forming part of the second receiver section of the second radar section 60 a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the second down-converting mixer 46b; generating by a second analog-to-digital converter 50b forming part of the second radar section 60 a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the second intermediate frequency (IF) filter 48b; and generating by a radar signal processor 66 forming part of the architecture of the FMCW MIMO radar 56 one or more signals relating to the velocity and range of the object illuminated by the transmit signal of at least one of the first radar section 58 and the at least second radar section 60 in response to the digitized filtered intermediate frequency (IF) signal generated by the first analog-to-digital converter 50a of the first radar section 58 and the digitized filtered intermediate frequency (IF) signal generated by the second analog-to-digital converter 50b of the at least second radar section 60.

[0113] In the third method, the chirped local oscillator signal generated by the first RF signal generator 30a of the first synthesizer 28a of the first transmitter section of the first radar section 58 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0114] In the third method, the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the first radar section 58, when mixed by the first up-converting mixer 34a of the first radar section 58 with the chirped local oscillator signal generated by the first RF signal generator 30a of the first radar section 58, causes the up- converted mixer signal generated by the first up-converting mixer 34a to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0115] In the third method, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a time delay in the receive signal received by the first receiving antenna 42a of the first radar section 58, the time delay being compensated for in the radar signal processor 66.

[0116] In the third method, the first phase shift of the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the first radar section 58 introduces a corresponding phase shift in the receive signal received by the first receiving antenna 42a of the first radar section 58 substantially equal (for lossless reflective objects) to the predetermined first phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0117] In the third method, the chirped local oscillator signal generated by the second RF signal generator 30b of the second synthesizer 28b of the second transmitter section of the at least second radar section 60 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0118] In the third method, the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the at least second radar section 60, when mixed by the second up-converting mixer 34b of the at least second radar section 60 with the chirped local oscillator signal generated by the second RF signal generator 30b of the at least second radar section 60, causes the up-converted mixer signal generated by the second up- converting mixer 34b to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0119] In the third method, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a time delay in the receive signal received by the second receiving antenna 42b of the at least second radar section 60, the time delay being compensated for in the radar signal processor 66.

[0120] In the third method, the second phase shift of the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the at least second radar section 60 introduces a corresponding phase shift in the receive signal received by the second receiving antenna 42b of the at least second radar section 60 substantially equal (for lossless reflective objects) to the predetermined second phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0121] In the third method, the first phase shift of the first phase-shifted frequency offset signal, being orthogonal to the second phase shift of the second phase-shifted frequency offset signal, minimizes cross-correlation between the receive signal received by the first receiving antenna 42a of the first radar section 58 and the receive signal received by the second receiving antenna 42b of the at least second radar section 60.

[0122] A fourth method of the present invention of suppressing local oscillator phase noise in a frequency modulated continuous wave (FMCW) multiple input, multiple output (MIMO) radar 56 having an architecture which includes a first radar section 58, a second radar section 60, a third radar section 62 and a fourth radar section 64, the first radar section 58 including a first transmitter section and a first receiver section, the second radar section 60 including a second transmitter section and a second receiver section, the third radar section 62 including a third transmitter section and a third receiver section, the fourth radar section 64 including a fourth transmitter section and a fourth receiver section, may include the steps of generating by a common frequency offset signal generator 36a a frequency offset signal having a known and fixed frequency offset; generating by a common multibit phase shifter 54a a first phase-shifted frequency offset signal, a second phase-shifted frequency offset signal, a third phase-shifted frequency offset signal and a fourth phase-shifted frequency offset signal in response to the frequency offset signal generated by the common frequency offset signal generator 36a, the common multibit phase shifter 54a having a first output, a second output, a third output and a fourth output, the common multibit phase shifter 54a generating the first phase-shifted frequency offset signal on the first output thereof, the second phase-shifted frequency offset signal on the second output thereof, the third phase-shifted frequency offset signal on the third output thereof and the fourth phase-shifted frequency offset signal on the fourth output thereof, the first phase- shifted frequency offset signal having a first phase shift, the second phase-shifted frequency offset signal having a second phase shift, the third phase-shifted frequency offset signal having a third phase shift and the fourth phase-shifted frequency offset signal having a fourth phase shift, the first phase shift being orthogonal to the second phase shift, the second phase shift being orthogonal to the third phase shift, the third phase shift being orthogonal to the fourth phase shift; generating by a common reference clock 70 a clock signal; generating by a first ramp generator 32a defining a component of a first synthesizer 28a forming part of the first transmitter section of the first radar section 58 a ramp-like signal in response to the clock signal; generating by a first RF (radio frequency) signal generator 30a defining a component of the first synthesizer 28a forming part of the first transmitter section of the first radar section 58 a chirped local oscillator signal in response to the ramp-like signal generated by the first ramp generator 32a; generating by a first up-converting mixer 34a forming part of the first transmitter section of the first radar section 58 an up-converted mixer signal in response to the chirped local oscillator signal generated by the first RF signal generator 30a and in response to the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a; generating by a first power amplifier 38a forming part of the first transmitter section of the first radar section 58 an amplified signal in response to the up-converted mixer signal generated by the first up- converting mixer 34a; transmitting by a first transmitting antenna 40a forming part of the first transmitter section of the first radar section 58 a transmit signal in response to the amplified signal generated by the first power amplifier 38a; receiving by a first receiving antenna 42a forming part of the first receiver section of the first radar section 58 a receive signal reflected from an object illuminated by the transmit signal transmitted by the first transmitting antenna 40a and generating a receive antenna output signal in response thereto; generating by a first low noise amplifier 44a forming part of the first receiver section of the first radar section 58 an amplified received signal in response to the receive antenna output signal generated by the first receiving antenna 42a; generating by a first down-converting mixer 46a forming part of the first receiver section of the first radar section 58 an intermediate frequency (IF) signal in response to the amplified received signal generated by the first low noise amplifier 44a and in response to the chirped local oscillator signal generated by the first RF signal generator 30a; generating by a first intermediate frequency (IF) filter 48a forming part of the first receiver section of the first radar section 58 a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the first down-converting mixer 46a; generating by a first analog-to- digital converter 50a forming part of the first radar section 58 a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the first intermediate frequency (IF) filter 48a; generating by a second ramp generator 32b defining a component of a second synthesizer 28b forming part of the second transmitter section of the second radar section 60 a ramp-like signal in response to the clock signal; generating by a second RF (radio frequency) signal generator 30b defining a component of the second synthesizer 28b forming part of the second transmitter section of the second radar section 60 a chirped local oscillator signal in response to the ramp-like signal generated by the second ramp generator 32b; generating by a second up-converting mixer 34b forming part of the second transmitter section of the second radar section 60 an up-converted mixer signal in response to the chirped local oscillator signal generated by the second RF signal generator 30b and in response to the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a; generating by a second power amplifier 38b forming part of the second transmitter section of the second radar section 60 an amplified signal in response to the up-converted mixer signal generated by the second up-converting mixer 34b; transmitting by a second transmitting antenna 40b forming part of the second transmitter section of the second radar section 60 a transmit signal in response to the amplified signal generated by the second power amplifier 38b; receiving by a second receiving antenna 42b forming part of the second receiver section of the second radar section 60 a receive signal reflected from an object illuminated by the transmit signal transmitted by the second transmitting antenna 40b and generating a receive antenna output signal in response thereto; generating by a second low noise amplifier 44b forming part of the second receiver section of the second radar section 60 an amplified received signal in response to the receive antenna output signal generated by the second receiving antenna 42b; generating by a second down-converting mixer 46b forming part of the second receiver section of the second radar section 60 an intermediate frequency (IF) signal in response to the amplified received signal generated by the second low noise amplifier 44b and in response to the chirped local oscillator signal generated by the second RF signal generator 30b; generating by a second intermediate frequency (IF) filter 48b forming part of the second receiver section of the second radar section 60 a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the second down-converting mixer 46b; generating by a second analog-to-digital converter 50b forming part of the second radar section 60 a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the second intermediate frequency (IF) filter 48b; generating by a third ramp generator 32c defining a component of a third synthesizer 28c forming part of the third transmitter section of the third radar section 62 a ramp-like signal in response to the clock signal; generating by a third RF (radio frequency) signal generator 30c defining a component of the third synthesizer 28c forming part of the third transmitter section of the third radar section 62 a chirped local oscillator signal in response to the ramp-like signal generated by the third ramp generator 32c; generating by a third up-converting mixer 34c forming part of the third transmitter section of the third radar section 62 an up-converted mixer signal in response to the chirped local oscillator signal generated by the third RF signal generator 30c and in response to the third phase-shifted frequency offset signal generated by the common multibit phase shifter 54a; generating by a third power amplifier 38c forming part of the third transmitter section of the third radar section 62 an amplified signal in response to the up-converted mixer signal generated by the third up-converting mixer 34c; transmitting by a third transmitting antenna 40c forming part of the third transmitter section of the third radar section 62 a transmit signal in response to the amplified signal generated by the third power amplifier 38c; receiving by a third receiving antenna 42c forming part of the third receiver section of the third radar section 62 a receive signal reflected from an object illuminated by the transmit signal transmitted by the third transmitting antenna 40c and generating a receive antenna output signal in response thereto; generating by a third low noise amplifier 44c forming part of the third receiver section of the third radar section 62 an amplified received signal in response to the receive antenna output signal generated by the third receiving antenna 42c; generating by a third down-converting mixer 46c forming part of the third receiver section of the third radar section 62 an intermediate frequency (IF) signal in response to the amplified received signal generated by the third low noise amplifier 44c and in response to the chirped local oscillator signal generated by the third RF signal generator 30c; generating by a third intermediate frequency (IF) filter 48c forming part of the third receiver section of the third radar section 62 a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the third downconverting mixer 46c; generating by a third analog-to-digital converter 50c forming part of the third radar section 62 a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the third intermediate frequency (IF) filter 48c; generating by a fourth ramp generator 32d defining a component of a fourth synthesizer 28d forming part of the fourth transmitter section of the fourth radar section 64 a ramp-like signal in response to the clock signal; generating by a fourth RF (radio frequency) signal generator 30d defining a component of the fourth synthesizer 28d forming part of the fourth transmitter section of the fourth radar section 64 a chirped local oscillator signal in response to the ramp-like signal generated by the fourth ramp generator 32d; generating by a fourth up-converting mixer 34d forming part of the fourth transmitter section of the fourth radar section 64 an up-converted mixer signal in response to the chirped local oscillator signal generated by the fourth RF signal generator 30d and in response to the fourth phase-shifted frequency offset signal generated by the common multibit phase shifter 54a; generating by a fourth power amplifier 38d forming part of the fourth transmitter section of the fourth radar section 64 an amplified signal in response to the up-converted mixer signal generated by the fourth up-converting mixer 34d; transmitting by a fourth transmitting antenna 40d forming part of the fourth transmitter section of the fourth radar section 64 a transmit signal in response to the amplified signal generated by the fourth power amplifier 38d; receiving by a fourth receiving antenna 42d forming part of the fourth receiver section of the fourth radar section 64 a receive signal reflected from an object illuminated by the transmit signal transmitted by the fourth transmitting antenna 40d and generating a receive antenna output signal in response thereto; generating by a fourth low noise amplifier 44d forming part of the fourth receiver section of the fourth radar section 64 an amplified received signal in response to the receive antenna output signal generated by the fourth receiving antenna 42d; generating by a fourth down-converting mixer 46d forming part of the fourth receiver section of the fourth radar section 64 an intermediate frequency (IF) signal in response to the amplified received signal generated by the fourth low noise amplifier 44d and in response to the chirped local oscillator signal generated by the fourth RF signal generator 30d; generating by a fourth intermediate frequency (IF) filter 48d forming part of the fourth receiver section of the fourth radar section 64 a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the fourth down-converting mixer 46d; generating by a fourth analog-to-digital converter 50d forming part of the fourth radar section 64 a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the fourth intermediate frequency (IF) filter 48d; and generating by a radar signal processor 66 forming part of the architecture of the FMCW MIMO radar 56 one or more signals relating to the velocity and range of the object illuminated by the transmit signal of at least one of the first radar section 58, the second radar section 60, the third radar section 62 and the fourth radar section 64 in response to the digitized filtered intermediate frequency (IF) signal generated by the first analog-to-digital converter 50a of the first radar section 58, the digitized filtered intermediate frequency (IF) signal generated by the second analog-to-digital converter 50b of the second radar section 60, the digitized filtered intermediate frequency (IF) signal generated by the third analog-to-digital converter 50c of the third radar section 62 and the digitized filtered intermediate frequency (IF) signal generated by the fourth analog-to-digital converter 50d of the fourth radar section 64.

[0123] In the fourth method, the chirped local oscillator signal generated by the first RF signal generator 30a of the first synthesizer 28a of the first transmitter section of the first radar section 58 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0124] In the fourth method, the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the first radar section 58, when mixed by the first up-converting mixer 34a of the first radar section 58 with the chirped local oscillator signal generated by the first RF signal generator 30a of the first radar section 58, causes the up- converted mixer signal generated by the first up-converting mixer 34a to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0125] In the fourth method, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a known time delay in the receive signal received by the first receiving antenna 42a of the first radar section 58, the time delay being compensated for in the radar signal processor 66.

[0126] In the fourth method, the first phase shift of the first phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the first radar section 58 introduces a corresponding phase shift in the receive signal received by the first receiving antenna 42a of the first radar section 58 substantially equal (for lossless reflective objects) to the predetermined first phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0127] In the fourth method, the chirped local oscillator signal generated by the second RF signal generator 30b of the second synthesizer 28b of the second transmitter section of the second radar section 60 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0128] In the fourth method, the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the second radar section 60, when mixed by the second up-converting mixer 34b of the second radar section 60 with the chirped local oscillator signal generated by the second RF signal generator 30b of the second radar section 60, causes the up-converted mixer signal generated by the second up-converting mixer 34b to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0129] In the fourth method, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a time delay in the receive signal received by the second receiving antenna 42b of the second radar section 60, the time delay being compensated for in the radar signal processor 66.

[0130] In the fourth method, the second phase shift of the second phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the second radar section 60 introduces a corresponding phase shift in the receive signal received by the second receiving antenna 42b of the second radar section 60 substantially equal (for lossless reflective objects) to the predetermined second phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0131] In the fourth method, the chirped local oscillator signal generated by the third RF signal generator 30c of the third synthesizer 28c of the third transmitter section of the third radar section 62 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0132] In the fourth method, the third phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the third radar section 62, when mixed by the third up-converting mixer 34c of the third radar section 62 with the chirped local oscillator signal generated by the third RF signal generator 30c of the third radar section 62, causes the up- converted mixer signal generated by the third up-converting mixer 34c to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset. In the fourth method, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a time delay in the receive signal received by the third receiving antenna 42c of the third radar section 62, the time delay being compensated for in the radar signal processor 66.

[0133] In the fourth method, the third phase shift of the third phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the third radar section 62 introduces a corresponding phase shift in the receive signal received by the third receiving antenna 42c of the third radar section 62 substantially equal (for lossless reflective objects) to the predetermined third phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0134] In the fourth method, the chirped local oscillator signal generated by the fourth RF signal generator 30d of the fourth synthesizer 28d of the fourth transmitter section of the fourth radar section 64 has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range.

[0135] In the fourth method, the fourth phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the fourth radar section 64, when mixed by the fourth up-converting mixer 34d of the fourth radar section 64 with the chirped local oscillator signal generated by the fourth RF signal generator 30d of the fourth radar section 64, causes the up-converted mixer signal generated by the fourth up-converting mixer 34d to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset.

[0136] In the fourth method, the frequency offset signal generated by the common frequency offset signal generator 36a introduces a time delay in the receive signal received by the fourth receiving antenna 42d of the fourth radar section 64, the time delay being compensated for in the radar signal processor 66. In the fourth method, the fourth phase shift of the fourth phase-shifted frequency offset signal generated by the common multibit phase shifter 54a and provided to the fourth radar section 64 introduces a corresponding phase shift in the receive signal received by the fourth receiving antenna 42d of the fourth radar section 64 substantially equal (for lossless reflective objects) to the predetermined fourth phase shift caused by the common multibit phase shifter 54a, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor 66.

[0137] In the fourth method, the first phase shift of the first phase-shifted frequency offset signal, being orthogonal to the second phase shift of the second phase-shifted frequency offset signal, the second phase shift of the second phase-shifted frequency offset signal, being orthogonal to the third phase shift of the third phase-shifted frequency offset signal, and the third phase shift of the third phase-shifted frequency offset signal, being orthogonal to the fourth phase shift of the fourth phase-shifted frequency offset signal, minimizes cross-correlation between the receive signal received by the first receiving antenna 42a of the first radar section 58, the receive signal received by the second receiving antenna 42b of the second radar section 60, the receive signal received by the third receiving antenna 42c of the third radar section 62 and the receive signal received by the fourth receiving antenna 42d of the fourth radar section 64.

[0138] Although illustrative embodiments of the present disclosure have been described herein with reference to the accompanying drawings, it is to be understood that the disclosure is not limited to those precise embodiments, and that various other changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the disclosure.

Claims

What is claimed is:

1. A frequency modulated continuous wave (FMCW) radar having an architecture, the architecture comprising: a transmitter section and a receiver section, the transmitter section including: a synthesizer having a ramp generator and an RF (radio frequency) signal generator, the ramp generator generating a ramp-like signal, the RF signal generator being responsive to the ramp-like signal generated by the ramp generator and generating a chirped local oscillator signal in response thereto; a frequency offset signal generator, the frequency offset signal generator generating a frequency offset signal having a known and fixed frequency offset; an up-converting mixer, the up-converting mixer being responsive to the chirped local oscillator signal generated by the RF signal generator and being responsive to the frequency offset signal generated by the frequency offset signal generator and generating an up-converted mixer signal in response to the chirped local oscillator signal and the frequency offset signal; a power amplifier, the power amplifier being responsive to the up-converted mixer signal generated by the up-converting mixer and generating an amplified signal in response thereto; and a transmitting antenna, the transmitting antenna being responsive to the amplified signal generated by the power amplifier and transmitting a transmit signal in response thereto; the receiver section including: a receiving antenna, the receiving antenna receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a low noise amplifier, the low noise amplifier being responsive to the receive antenna output signal generated by the receiving antenna and generating an amplified received signal in response thereto;a down-converting mixer, the down-converting mixer being responsive to the amplified received signal generated by the low noise amplifier and being responsive to the chirped local oscillator signal generated by the RF signal generator and generating an intermediate frequency (IF) signal (also referred to as a beat frequency) in response to the amplified received signal and the chirped local oscillator signal; an intermediate frequency (IF) filter, the intermediate frequency (IF) filter being responsive to the intermediate frequency (IF) signal generated by the down-converting mixer and generating a filtered intermediate frequency (IF) signal in response thereto; an analog-to-digital converter, the analog-to-digital converter being responsive to the filtered intermediate frequency (IF) signal generated by the intermediate frequency (IF) filter and generating a digitized filtered intermediate frequency (IF) signal in response thereto; and a radar signal processor, the radar signal processor being responsive to the digitized filtered intermediate frequency (IF) signal generated by the analog-to-digital converter and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of the radar; wherein the chirped local oscillator signal generated by the RF signal generator of the synthesizer of the transmitter section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the frequency offset signal generated by the frequency offset signal generator, when mixed by the up-converting mixer with the chirped local oscillator signal generated by the RF signal generator, causes the up-converted mixer signal to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; and wherein the frequency offset signal generated by the frequency offset signal generator introduces a time delay in the receive signal received by the receiving antenna, the time delay being compensated for in the radar signal processor.

2. A frequency modulated continuous wave (FMCW) radar having an architecture, the architecture comprising: a transmitter section and a receiver section, the transmitter section including: a synthesizer having a ramp generator and an RF (radio frequency) signal generator, the ramp generator generating a ramp-like signal, the RF signal generator being responsive to the ramp-like signal generated by the ramp generator and generating a chirped local oscillator signal in response thereto; a frequency offset signal generator, the frequency offset signal generator generating a frequency offset signal having a known and fixed frequency offset; a phase shifter, the phase shifter being responsive to the frequency offset signal generated by the frequency offset signal generator and generating a phase-shifted frequency offset signal in response thereto, the phase-shifted frequency offset signal corresponding to the frequency offset signal shifted in phase by a predetermined phase shift; an up-converting mixer, the up-converting mixer being responsive to the chirped local oscillator signal generated by the RF signal generator and being responsive to the phase-shifted frequency offset signal generated by the phase shifter and generating an up-converted mixer signal in response to the chirped local oscillator signal and the phase-shifted frequency offset signal; a power amplifier, the power amplifier being responsive to the up-converted mixer signal generated by the up-converting mixer and generating an amplified signal in response thereto; and a transmitting antenna, the transmitting antenna being responsive to the amplified signal generated by the power amplifier and transmitting a transmit signal in response thereto; the receiver section including: a receiving antenna, the receiving antenna receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto;a low noise amplifier, the low noise amplifier being responsive to the receive antenna output signal generated by the receiving antenna and generating an amplified received signal in response thereto; a down-converting mixer, the down-converting mixer being responsive to the amplified received signal generated by the low noise amplifier and being responsive to the chirped local oscillator signal generated by the RF signal generator and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; an intermediate frequency (IF) filter, the intermediate frequency (IF) filter being responsive to the intermediate frequency (IF) signal generated by the down-converting mixer and generating a filtered intermediate frequency (IF) signal in response thereto; an analog-to-digital converter, the analog-to-digital converter being responsive to the filtered intermediate frequency (IF) signal generated by the intermediate frequency (IF) filter and generating a digitized filtered intermediate frequency (IF) signal in response thereto; and a radar signal processor, the radar signal processor being responsive to the digitized filtered intermediate frequency (IF) signal generated by the analog-to-digital converter and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of the radar; wherein the chirped local oscillator signal generated by the RF signal generator of the synthesizer of the transmitter section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the phase-shifted frequency offset signal generated by the phase shifter, when mixed by the up-converting mixer with the chirped local oscillator signal generated by the RF signal generator, causes the up-converted mixer signal to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset;wherein the frequency offset signal generated by the frequency offset signal generator introduces a time delay in the receive signal received by the receiving antenna, the time delay being compensated for in the radar signal processor; and wherein the phase-shifted frequency offset signal generated by the phase shifter introduces a corresponding phase shift in the receive signal received by the receiving antenna substantially equal to the predetermined phase shift caused by the phase shifter, the phase shift in the receive signal being compensated for in the radar signal processor.

3. A frequency modulated continuous wave (FMCW) multiple input, multiple output (MIMO) radar having an architecture, the architecture comprising: a common frequency offset signal generator, the common frequency offset signal generator generating a frequency offset signal having a known and fixed frequency offset; a common multibit phase shifter, the common multibit phase shifter having a first output and at least a second output, the common multibit phase shifter being responsive to the frequency offset signal generated by the common frequency offset signal generator and generating a first phase-shifted frequency offset signal on the first output thereof and at least a second phase- shifted frequency offset signal on the at least second output thereof, the first phase-shifted frequency offset signal having a first phase shift, the at least second phase-shifted frequency offset signal having a second phase shift, the first phase shift being orthogonal to the second phase shift; a common reference clock, the common reference clock generating a clock signal; and a first radar section and at least a second radar section; wherein the first radar section includes a first transmitter section and a first receiver section, the first transmitter section of the first radar section including: a first synthesizer having a first ramp generator and a first RF (radio frequency) signal generator, the first ramp generator generating a ramp-like signal, the clock signal generated by the common reference clock being provided to the first ramp generator, the first RF signal generator being responsive to the ramp-like signal generated by the first ramp generator and generating a chirped local oscillator signal in response thereto;a first up-converting mixer, the first up-converting mixer being responsive to the chirped local oscillator signal generated by the first RF signal generator and being responsive to the first phase-shifted frequency offset signal generated by the common multibit phase shifter and generating an up-converted mixer signal in response to the chirped local oscillator signal and the first phase-shifted frequency offset signal; a first power amplifier, the first power amplifier being responsive to the up-converted mixer signal generated by the first up-converting mixer and generating an amplified signal in response thereto; and a first transmitting antenna, the first transmitting antenna being responsive to the amplified signal generated by the first power amplifier and transmitting a transmit signal in response thereto; the receiver section of the first radar section including: a first receiving antenna, the first receiving antenna receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a first low noise amplifier, the first low noise amplifier being responsive to the receive antenna output signal generated by the first receiving antenna and generating an amplified received signal in response thereto; a first down-converting mixer, the first down-converting mixer being responsive to the amplified received signal generated by the first low noise amplifier and being responsive to the chirped local oscillator signal generated by the first RF signal generator and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a first intermediate frequency (IF) filter, the first intermediate frequency (IF) filter being responsive to the intermediate frequency (IF) signal generated by the first down-converting mixer and generating a filtered intermediate frequency (IF) signal in response thereto; anda first analog-to-digital converter, the first analog-to-digital converter being responsive to the filtered intermediate frequency (IF) signal generated by the first intermediate frequency (IF) filter and generating a digitized filtered intermediate frequency (IF) signal in response thereto; wherein the at least second radar section includes a second transmitter section and a second receiver section, the second transmitter section of the at least second radar section including: a second synthesizer having a second ramp generator and a second RF (radio frequency) signal generator, the second ramp generator generating a ramp-like signal, the clock signal generated by the common reference clock being provided to the second ramp generator, the second RF signal generator being responsive to the ramp-like signal generated by the second ramp generator and generating a chirped local oscillator signal in response thereto; a second up-converting mixer, the second up-converting mixer being responsive to the chirped local oscillator signal generated by the second RF signal generator and being responsive to the second phase-shifted frequency offset signal generated by the common multibit phase shifter and generating an up-converted mixer signal in response to the chirped local oscillator signal and the second phase-shifted frequency offset signal; a second power amplifier, the second power amplifier being responsive to the up- converted mixer signal generated by the second up-converting mixer and generating an amplified signal in response thereto; and a second transmitting antenna, the second transmitting antenna being responsive to the amplified signal generated by the second power amplifier and transmitting a transmit signal in response thereto; the receiver section of the at least second radar section including: a second receiving antenna, the second receiving antenna receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto;a second low noise amplifier, the second low noise amplifier being responsive to the receive antenna output signal generated by the second receiving antenna and generating an amplified received signal in response thereto; a second down-converting mixer, the second down-converting mixer being responsive to the amplified received signal generated by the second low noise amplifier and being responsive to the chirped local oscillator signal generated by the second RF signal generator and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a second intermediate frequency (IF) filter, the second intermediate frequency (IF) filter being responsive to the intermediate frequency (IF) signal generated by the second downconverting mixer and generating a filtered intermediate frequency (IF) signal in response thereto; and a second analog-to-digital converter, the second analog-to-digital converter being responsive to the filtered intermediate frequency (IF) signal generated by the second intermediate frequency (IF) filter and generating a digitized filtered intermediate frequency (IF) signal in response thereto; wherein the architecture of the FMCW MIMO radar further includes: a radar signal processor, the radar signal processor being responsive to the digitized filtered intermediate frequency (IF) signal generated by the first analog-to-digital converter of the first radar section and the digitized filtered intermediate frequency (IF) signal generated by the second analog-to-digital converter of the at least second radar section and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of at least one of the first radar section and the at least second radar section; wherein the chirped local oscillator signal generated by the first RF signal generator of the first synthesizer of the first transmitter section of the first radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequencyrange in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the first phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the first radar section, when mixed by the first up-converting mixer of the first radar section with the chirped local oscillator signal generated by the first RF signal generator of the first radar section, causes the up-converted mixer signal generated by the first up-converting mixer to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a time delay in the receive signal received by the first receiving antenna of the first radar section, the time delay being compensated for in the radar signal processor; wherein the first phase shift of the first phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the first radar section introduces a corresponding phase shift in the receive signal received by the first receiving antenna of the first radar section substantially equal (for lossless reflective objects) to the predetermined first phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; wherein the chirped local oscillator signal generated by the second RF signal generator of the second synthesizer of the second transmitter section of the at least second radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the second phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the at least second radar section, when mixed by the second up-converting mixer of the at least second radar section with the chirped local oscillator signal generated by the second RF signal generator of the at least second radar section, causes the up-converted mixer signal generated by the second up-converting mixer to include phasenoise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a time delay in the receive signal received by the second receiving antenna of the at least second radar section, the time delay being compensated for in the radar signal processor; wherein the second phase shift of the second phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the at least second radar section introduces a corresponding phase shift in the receive signal received by the second receiving antenna of the at least second radar section substantially equal (for lossless reflective objects) to the predetermined second phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; and wherein the first phase shift of the first phase-shifted frequency offset signal, being orthogonal to the second phase shift of the second phase-shifted frequency offset signal, minimizes cross-correlation between the receive signal received by the first receiving antenna of the first radar section and the receive signal received by the second receiving antenna of the at least second radar section.

4. A frequency modulated continuous wave (FMCW) multiple input, multiple output (MIMO) radar having an architecture, the architecture comprising: a common frequency offset signal generator, the common frequency offset signal generator generating a frequency offset signal having a known and fixed frequency offset; a common multibit phase shifter, the common multibit phase shifter having a first output, a second output, a third output and a fourth output, the common multibit phase shifter being responsive to the frequency offset signal generated by the common frequency offset signal generator and generating a first phase-shifted frequency offset signal on the first output thereof, a second phase-shifted frequency offset signal on the second output thereof, a third phase-shifted frequency offset signal on the third output thereof and a fourth phase-shifted frequency offset signal on the fourth output thereof, the first phase-shifted frequency offset signal having a firstphase shift, the second phase-shifted frequency offset signal having a second phase shift, the third phase-shifted frequency offset signal having a third phase shift and the fourth phase-shifted frequency offset signal having a fourth phase shift, the first phase shift being orthogonal to the second phase shift, the second phase shift being orthogonal to the third phase shift, the third phase shift being orthogonal to the fourth phase shift; a common reference clock, the common reference clock generating a clock signal; a first radar section, a second radar section, a third radar section and a fourth radar section; wherein the first radar section includes a first transmitter section and a first receiver section, the first transmitter section of the first radar section including: a first synthesizer having a first ramp generator and a first RF (radio frequency) signal generator, the first ramp generator generating a ramp-like signal, the clock signal generated by the common reference clock being provided to the first ramp generator, the first RF signal generator being responsive to the ramp-like signal generated by the first ramp generator and generating a chirped local oscillator signal in response thereto; a first up-converting mixer, the first up-converting mixer being responsive to the chirped local oscillator signal generated by the first RF signal generator and being responsive to the first phase-shifted frequency offset signal generated by the common multibit phase shifter and generating an up-converted mixer signal in response to the chirped local oscillator signal and the first phase-shifted frequency offset signal; a first power amplifier, the first power amplifier being responsive to the up-converted mixer signal generated by the first up-converting mixer and generating an amplified signal in response thereto; and a first transmitting antenna, the first transmitting antenna being responsive to the amplified signal generated by the first power amplifier and transmitting a transmit signal in response thereto; the receiver section of the first radar section including:a first receiving antenna, the first receiving antenna receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a first low noise amplifier, the first low noise amplifier being responsive to the receive antenna output signal generated by the first receiving antenna and generating an amplified received signal in response thereto; a first down-converting mixer, the first down-converting mixer being responsive to the amplified received signal generated by the first low noise amplifier and being responsive to the chirped local oscillator signal generated by the first RF signal generator and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a first intermediate frequency (IF) filter, the first intermediate frequency (IF) filter being responsive to the intermediate frequency (IF) signal generated by the first down-converting mixer and generating a filtered intermediate frequency (IF) signal in response thereto; and a first analog-to-digital converter, the first analog-to-digital converter being responsive to the filtered intermediate frequency (IF) signal generated by the first intermediate frequency (IF) filter and generating a digitized filtered intermediate frequency (IF) signal in response thereto; wherein the second radar section includes a second transmitter section and a second receiver section, the second transmitter section of the second radar section including: a second synthesizer having a second ramp generator and a second RF (radio frequency) signal generator, the second ramp generator generating a ramp-like signal, the clock signal generated by the common reference clock being provided to the second ramp generator, the second RF signal generator being responsive to the ramp-like signal generated by the second ramp generator and generating a chirped local oscillator signal in response thereto; a second up-converting mixer, the second up-converting mixer being responsive to the chirped local oscillator signal generated by the second RF signal generator and being responsive to the second phase-shifted frequency offset signal generated by the common multibit phaseshifter and generating an up-converted mixer signal in response to the chirped local oscillator signal and the second phase-shifted frequency offset signal; a second power amplifier, the second power amplifier being responsive to the up- converted mixer signal generated by the second up-converting mixer and generating an amplified signal in response thereto; and a second transmitting antenna, the second transmitting antenna being responsive to the amplified signal generated by the second power amplifier and transmitting a transmit signal in response thereto; the receiver section of the second radar section including: a second receiving antenna, the second receiving antenna receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a second low noise amplifier, the second low noise amplifier being responsive to the receive antenna output signal generated by the second receiving antenna and generating an amplified received signal in response thereto; a second down-converting mixer, the second down-converting mixer being responsive to the amplified received signal generated by the second low noise amplifier and being responsive to the chirped local oscillator signal generated by the second RF signal generator and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a second intermediate frequency (IF) filter, the second intermediate frequency (IF) filter being responsive to the intermediate frequency (IF) signal generated by the second downconverting mixer and generating a filtered intermediate frequency (IF) signal in response thereto; and a second analog-to-digital converter, the second analog-to-digital converter being responsive to the filtered intermediate frequency (IF) signal generated by the second intermediate frequency (IF) filter and generating a digitized filtered intermediate frequency (IF) signal in response thereto;wherein the third radar section includes a third transmitter section and a third receiver section, the third transmitter section of the third radar section including: a third synthesizer having a third ramp generator and a third RF (radio frequency) signal generator, the third ramp generator generating a ramp-like signal, the clock signal generated by the common reference clock being provided to the third ramp generator, the third RF signal generator being responsive to the ramp-like signal generated by the third ramp generator and generating a chirped local oscillator signal in response thereto; a third up-converting mixer, the third up-converting mixer being responsive to the chirped local oscillator signal generated by the third RF signal generator and being responsive to the third phase-shifted frequency offset signal generated by the common multibit phase shifter and generating an up-converted mixer signal in response to the chirped local oscillator signal and the third phase-shifted frequency offset signal; a third power amplifier, the third power amplifier being responsive to the up-converted mixer signal generated by the third up-converting mixer and generating an amplified signal in response thereto; and a third transmitting antenna, the third transmitting antenna being responsive to the amplified signal generated by the third power amplifier and transmitting a transmit signal in response thereto; the receiver section of the third radar section including: a third receiving antenna, the third receiving antenna receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a third low noise amplifier, the third low noise amplifier being responsive to the receive antenna output signal generated by the third receiving antenna and generating an amplified received signal in response thereto; a third down-converting mixer, the third down-converting mixer being responsive to the amplified received signal generated by the third low noise amplifier and being responsive to the chirped local oscillator signal generated by the third RF signal generator and generating anintermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a third intermediate frequency (IF) filter, the third intermediate frequency (IF) filter being responsive to the intermediate frequency (IF) signal generated by the third down-converting mixer and generating a filtered intermediate frequency (IF) signal in response thereto; and a third analog-to-digital converter, the third analog-to-digital converter being responsive to the filtered intermediate frequency (IF) signal generated by the third intermediate frequency (IF) filter and generating a digitized filtered intermediate frequency (IF) signal in response thereto; wherein the fourth radar section includes a fourth transmitter section and a fourth receiver section, the fourth transmitter section of the fourth radar section including: a fourth synthesizer having a fourth ramp generator and a fourth RF (radio frequency) signal generator, the fourth ramp generator generating a ramp-like signal, the clock signal generated by the common reference clock being provided to the fourth ramp generator, the fourth RF signal generator being responsive to the ramp-like signal generated by the fourth ramp generator and generating a chirped local oscillator signal in response thereto; a fourth up-converting mixer, the fourth up-converting mixer being responsive to the chirped local oscillator signal generated by the fourth RF signal generator and being responsive to the fourth phase-shifted frequency offset signal generated by the common multibit phase shifter and generating an up-converted mixer signal in response to the chirped local oscillator signal and the fourth phase-shifted frequency offset signal; a fourth power amplifier, the fourth power amplifier being responsive to the up-converted mixer signal generated by the fourth up-converting mixer and generating an amplified signal in response thereto; and a fourth transmitting antenna, the fourth transmitting antenna being responsive to the amplified signal generated by the fourth power amplifier and transmitting a transmit signal in response thereto; the receiver section of the fourth radar section including:a fourth receiving antenna, the fourth receiving antenna receiving a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; a fourth low noise amplifier, the fourth low noise amplifier being responsive to the receive antenna output signal generated by the fourth receiving antenna and generating an amplified received signal in response thereto; a fourth down-converting mixer, the fourth down-converting mixer being responsive to the amplified received signal generated by the fourth low noise amplifier and being responsive to the chirped local oscillator signal generated by the fourth RF signal generator and generating an intermediate frequency (IF) signal in response to the amplified received signal and the chirped local oscillator signal; a fourth intermediate frequency (IF) filter, the fourth intermediate frequency (IF) filter being responsive to the intermediate frequency (IF) signal generated by the fourth downconverting mixer and generating a filtered intermediate frequency (IF) signal in response thereto; and a fourth analog-to-digital converter, the fourth analog-to-digital converter being responsive to the filtered intermediate frequency (IF) signal generated by the fourth intermediate frequency (IF) filter and generating a digitized filtered intermediate frequency (IF) signal in response thereto; wherein the architecture of the FMCW MIMO radar further includes: a radar signal processor, the radar signal processor being responsive to the digitized filtered intermediate frequency (IF) signal generated by the first analog-to-digital converter of the first radar section, the digitized filtered intermediate frequency (IF) signal generated by the second analog-to-digital converter of the second radar section, the digitized filtered intermediate frequency (IF) signal generated by the third analog-to-digital converter of the third radar section and the digitized filtered intermediate frequency (IF) signal generated by the fourth analog-to- digital converter of the fourth radar section and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of atleast one of the first radar section, the second radar section, the third radar section and the fourth radar section; wherein the chirped local oscillator signal generated by the first RF signal generator of the first synthesizer of the first transmitter section of the first radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the first phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the first radar section, when mixed by the first up-converting mixer of the first radar section with the chirped local oscillator signal generated by the first RF signal generator of the first radar section, causes the up-converted mixer signal generated by the first up-converting mixer to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a known time delay in the receive signal received by the first receiving antenna of the first radar section, the time delay being compensated for in the radar signal processor; wherein the first phase shift of the first phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the first radar section introduces a corresponding phase shift in the receive signal received by the first receiving antenna of the first radar section substantially equal (for lossless reflective objects) to the predetermined first phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; wherein the chirped local oscillator signal generated by the second RF signal generator of the second synthesizer of the second transmitter section of the second radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequencyrange in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the second phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the second radar section, when mixed by the second up- converting mixer of the second radar section with the chirped local oscillator signal generated by the second RF signal generator of the second radar section, causes the up-converted mixer signal generated by the second up-converting mixer to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a time delay in the receive signal received by the second receiving antenna of the second radar section, the time delay being compensated for in the radar signal processor; wherein the second phase shift of the second phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the second radar section introduces a corresponding phase shift in the receive signal received by the second receiving antenna of the second radar section substantially equal (for lossless reflective objects) to the predetermined second phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; and wherein the chirped local oscillator signal generated by the third RF signal generator of the third synthesizer of the third transmitter section of the third radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the third phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the third radar section, when mixed by the third up-converting mixer of the third radar section with the chirped local oscillator signal generated by the third RF signal generator of the third radar section, causes the up-converted mixer signal generated by thethird up-converting mixer to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a time delay in the receive signal received by the third receiving antenna of the third radar section, the time delay being compensated for in the radar signal processor; wherein the third phase shift of the third phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the third radar section introduces a corresponding phase shift in the receive signal received by the third receiving antenna of the third radar section substantially equal (for lossless reflective objects) to the predetermined third phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; wherein the chirped local oscillator signal generated by the fourth RF signal generator of the fourth synthesizer of the fourth transmitter section of the fourth radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the fourth phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the fourth radar section, when mixed by the fourth up- converting mixer of the fourth radar section with the chirped local oscillator signal generated by the fourth RF signal generator of the fourth radar section, causes the up-converted mixer signal generated by the fourth up-converting mixer to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a time delay in the receive signal received by the fourth receiving antenna of the fourth radar section, the time delay being compensated for in the radar signal processor; wherein the fourth phase shift of the fourth phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the fourth radar section introduces a corresponding phase shift in the receive signal received by the fourth receivingantenna of the fourth radar section substantially equal (for lossless reflective objects) to the predetermined fourth phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; and wherein the first phase shift of the first phase-shifted frequency offset signal, being orthogonal to the second phase shift of the second phase-shifted frequency offset signal, the second phase shift of the second phase-shifted frequency offset signal, being orthogonal to the third phase shift of the third phase-shifted frequency offset signal, and the third phase shift of the third phase-shifted frequency offset signal, being orthogonal to the fourth phase shift of the fourth phase-shifted frequency offset signal, minimizes cross-correlation between the receive signal received by the first receiving antenna of the first radar section, the receive signal received by the second receiving antenna of the second radar section, the receive signal received by the third receiving antenna of the third radar section and the receive signal received by the fourth receiving antenna of the fourth radar section.

5. A method of suppressing local oscillator phase noise in a frequency modulated continuous wave (FMCW) radar, which comprises the steps of: generating by a ramp generator a ramp-like signal; generating by an RF (radio frequency) signal generator a chirped local oscillator signal in response to the ramp-like signal; generating by a frequency offset signal generator a frequency offset signal having a known and fixed frequency offset; mixing by an up-converting mixer the chirped local oscillator signal and the frequency offset signal and generating an up-converted mixer signal in response thereto; generating by a power amplifier an amplified signal in response to the up-converted mixer signal; transmitting by a transmitting antenna a transmit signal in response to the amplified signal;receiving by a receiving antenna a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; generating by a low noise amplifier an amplified received signal in response to the receive antenna output signal; mixing by a down-converting mixer the amplified received signal and the chirped local oscillator signal and generating an intermediate frequency (IF) signal in response thereto; filtering by an intermediate frequency (IF) filter the intermediate frequency (IF) signal and generating a filtered intermediate frequency (IF) signal in response thereto; digitizing by an analog-to-digital converter the filtered intermediate frequency (IF) signal and generating a digitized filtered intermediate frequency (IF) signal in response thereto; and processing by a radar signal processor the digitized filtered intermediate frequency (IF) signal and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of the radar; wherein the chirped local oscillator signal generated by the RF signal generator has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the frequency offset signal generated by the frequency offset signal generator, when mixed by the up-converting mixer with the chirped local oscillator signal generated by the RF signal generator, causes the up-converted mixer signal to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; and wherein the frequency offset signal generated by the frequency offset signal generator introduces a time delay in the receive signal received by the receiving antenna, the time delay being compensated for in the radar signal processor.

6. A method of suppressing local oscillator phase noise in a frequency modulated continuous wave (FMCW) radar, which comprises the steps of:generating by a ramp generator a ramp-like signal; generating by an RF (radio frequency) signal generator a chirped local oscillator signal in response to the ramp-like signal; generating by a frequency offset signal generator a frequency offset signal having a known and fixed frequency offset; phase shifting by a phase shifter the frequency offset signal and generating a phase- shifted frequency offset signal in response thereto, the phase-shifted frequency offset signal corresponding to the frequency offset signal shifted in phase by a predetermined phase shift; mixing by an up-converting mixer the chirped local oscillator signal and the phase-shifted frequency offset signal and generating an up-converted mixer signal in response thereto; generating by a power amplifier an amplified signal in response to the up-converted mixer signal; transmitting by a transmitting antenna a transmit signal in response to the amplified signal; receiving by a receiving antenna a receive signal reflected from an object illuminated by the transmit signal and generating a receive antenna output signal in response thereto; generating by a low noise amplifier an amplified received signal in response to the receive antenna output signal; mixing by a down-converting mixer the amplified received signal and the chirped local oscillator signal and generating an intermediate frequency (IF) signal in response thereto; filtering by an intermediate frequency (IF) filter the intermediate frequency (IF) signal and generating a filtered intermediate frequency (IF) signal in response thereto; digitizing by an analog-to-digital converter the filtered intermediate frequency (IF) signal and generating a digitized filtered intermediate frequency (IF) signal in response thereto; andprocessing by a radar signal processor the digitized filtered intermediate frequency (IF) signal and generating in response thereto one or more signals relating to the velocity and range of the object illuminated by the transmit signal of the radar; wherein the chirped local oscillator signal generated by the RF signal generator has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the phase-shifted frequency offset signal generated by the phase shifter, when mixed by the up-converting mixer with the chirped local oscillator signal generated by the RF signal generator, causes the up-converted mixer signal to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the frequency offset signal generator introduces a time delay in the receive signal received by the receiving antenna, the time delay being compensated for in the radar signal processor; and wherein the phase-shifted frequency offset signal generated by the phase shifter introduces a phase shift in the receive signal received by the receiving antenna substantially equal to the predetermined phase shift caused by the phase shifter, the phase shift in the receive signal being compensated for in the radar signal processor.

7. A method of suppressing local oscillator phase noise in a frequency modulated continuous wave (FMCW) multiple input, multiple output (MIMO) radar, the frequency modulated continuous wave (FMCW) multiple input, multiple output (MIMO) radar having an architecture which includes a first radar section and at least a second radar section, the first radar section including a first transmitter section and a first receiver section, the at least second radar section including a second transmitter section and a second receiver section, the method comprising the steps of: generating by a common frequency offset signal generator a frequency offset signal having a known and fixed frequency offset;generating by a common multibit phase shifter a first phase-shifted frequency offset signal and at least a second phase-shifted frequency offset signal in response to the frequency offset signal generated by the common frequency offset signal generator, the common multibit phase shifter having a first output and at least a second output, the common multibit phase shifter generating the first phase-shifted frequency offset signal on the first output thereof and the at least second phase-shifted frequency offset signal on the at least second output thereof, the first phase-shifted frequency offset signal having a first phase shift, the at least second phase-shifted frequency offset signal having a second phase shift, the first phase shift being orthogonal to the second phase shift; generating by a common reference clock a clock signal; generating by a first ramp generator defining a component of a first synthesizer forming part of the first transmitter section of the first radar section a ramp-like signal in response to the clock signal; generating by a first RF (radio frequency) signal generator defining a component of the first synthesizer forming part of the first transmitter section of the first radar section a chirped local oscillator signal in response to the ramp-like signal generated by the first ramp generator; generating by a first up-converting mixer forming part of the first transmitter section of the first radar section an up-converted mixer signal in response to the chirped local oscillator signal generated by the first RF signal generator and in response to the first phase-shifted frequency offset signal generated by the common multibit phase shifter; generating by a first power amplifier forming part of the first transmitter section of the first radar section an amplified signal in response to the up-converted mixer signal generated by the first up-converting mixer; transmitting by a first transmitting antenna forming part of the first transmitter section of the first radar section a transmit signal in response to the amplified signal generated by the first power amplifier; receiving by a first receiving antenna forming part of the first receiver section of the first radar section a receive signal reflected from an object illuminated by the transmit signaltransmitted by the first transmitting antenna and generating a receive antenna output signal in response thereto; generating by a first low noise amplifier forming part of the first receiver section of the first radar section an amplified received signal in response to the receive antenna output signal generated by the first receiving antenna; generating by a first down-converting mixer forming part of the first receiver section of the first radar section an intermediate frequency (IF) signal in response to the amplified received signal generated by the first low noise amplifier and in response to the chirped local oscillator signal generated by the first RF signal generator; generating by a first intermediate frequency (IF) filter forming part of the first receiver section of the first radar section a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the first down-converting mixer; generating by a first analog-to-digital converter forming part of the first radar section a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the first intermediate frequency (IF) filter; generating by a second ramp generator defining a component of a second synthesizer forming part of the second transmitter section of the second radar section a ramp-like signal in response to the clock signal; generating by a second RF (radio frequency) signal generator defining a component of the second synthesizer forming part of the second transmitter section of the second radar section a chirped local oscillator signal in response to the ramp-like signal generated by the second ramp generator; generating by a second up-converting mixer forming part of the second transmitter section of the second radar section an up-converted mixer signal in response to the chirped local oscillator signal generated by the second RF signal generator and in response to the second phase-shifted frequency offset signal generated by the common multibit phase shifter;generating by a second power amplifier forming part of the second transmitter section of the second radar section an amplified signal in response to the up-converted mixer signal generated by the second up-converting mixer; transmitting by a second transmitting antenna forming part of the second transmitter section of the second radar section a transmit signal in response to the amplified signal generated by the second power amplifier; receiving by a second receiving antenna forming part of the second receiver section of the second radar section a receive signal reflected from an object illuminated by the transmit signal transmitted by the second transmitting antenna and generating a receive antenna output signal in response thereto; generating by a second low noise amplifier forming part of the second receiver section of the second radar section an amplified received signal in response to the receive antenna output signal generated by the second receiving antenna; generating by a second down-converting mixer forming part of the second receiver section of the second radar section an intermediate frequency (IF) signal in response to the amplified received signal generated by the second low noise amplifier and in response to the chirped local oscillator signal generated by the second RF signal generator; generating by a second intermediate frequency (IF) filter forming part of the second receiver section of the second radar section a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the second down-converting mixer; generating by a second analog-to-digital converter forming part of the second radar section a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the second intermediate frequency (IF) filter; and generating by a radar signal processor forming part of the architecture of the FMCW MIMO radar one or more signals relating to the velocity and range of the object illuminated by the transmit signal of at least one of the first radar section and the at least second radar section inresponse to the digitized filtered intermediate frequency (IF) signal generated by the first analog- to-digital converter of the first radar section and the digitized filtered intermediate frequency (IF) signal generated by the second analog-to-digital converter of the at least second radar section; wherein the chirped local oscillator signal generated by the first RF signal generator of the first synthesizer of the first transmitter section of the first radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the first phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the first radar section, when mixed by the first up-converting mixer of the first radar section with the chirped local oscillator signal generated by the first RF signal generator of the first radar section, causes the up-converted mixer signal generated by the first up-converting mixer to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a time delay in the receive signal received by the first receiving antenna of the first radar section, the time delay being compensated for in the radar signal processor; wherein the first phase shift of the first phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the first radar section introduces a corresponding phase shift in the receive signal received by the first receiving antenna of the first radar section substantially equal (for lossless reflective objects) to the predetermined first phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; wherein the chirped local oscillator signal generated by the second RF signal generator of the second synthesizer of the second transmitter section of the at least second radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peakfrequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the second phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the at least second radar section, when mixed by the second up-converting mixer of the at least second radar section with the chirped local oscillator signal generated by the second RF signal generator of the at least second radar section, causes the up-converted mixer signal generated by the second up-converting mixer to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a time delay in the receive signal received by the second receiving antenna of the at least second radar section, the time delay being compensated for in the radar signal processor; wherein the second phase shift of the second phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the at least second radar section introduces a corresponding phase shift in the receive signal received by the second receiving antenna of the at least second radar section substantially equal (for lossless reflective objects) to the predetermined second phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; and wherein the first phase shift of the first phase-shifted frequency offset signal, being orthogonal to the second phase shift of the second phase-shifted frequency offset signal, minimizes cross-correlation between the receive signal received by the first receiving antenna of the first radar section and the receive signal received by the second receiving antenna of the at least second radar section.

8. A method of suppressing local oscillator phase noise in a frequency modulated continuous wave (FMCW) multiple input, multiple output (MIMO) radar, the frequency modulated continuous wave (FMCW) multiple input, multiple output (MIMO) radar having an architecture which includes a first radar section, a second radar section, a third radar section anda fourth radar section, the first radar section including a first transmitter section and a first receiver section, the second radar section including a second transmitter section and a second receiver section, the third radar section including a third transmitter section and a third receiver section, the fourth radar section including a fourth transmitter section and a fourth receiver section, the method comprising the steps of: generating by a common frequency offset signal generator a frequency offset signal having a known and fixed frequency offset; generating by a common multibit phase shifter a first phase-shifted frequency offset signal, a second phase-shifted frequency offset signal, a third phase-shifted frequency offset signal and a fourth phase-shifted frequency offset signal in response to the frequency offset signal generated by the common frequency offset signal generator, the common multibit phase shifter having a first output, a second output, a third output and a fourth output, the common multibit phase shifter generating the first phase-shifted frequency offset signal on the first output thereof, the second phase-shifted frequency offset signal on the second output thereof, the third phase-shifted frequency offset signal on the third output thereof and the fourth phase-shifted frequency offset signal on the fourth output thereof, the first phase-shifted frequency offset signal having a first phase shift, the second phase-shifted frequency offset signal having a second phase shift, the third phase-shifted frequency offset signal having a third phase shift and the fourth phase-shifted frequency offset signal having a fourth phase shift, the first phase shift being orthogonal to the second phase shift, the second phase shift being orthogonal to the third phase shift, the third phase shift being orthogonal to the fourth phase shift; generating by a common reference clock a clock signal; generating by a first ramp generator defining a component of a first synthesizer forming part of the first transmitter section of the first radar section a ramp-like signal in response to the clock signal; generating by a first RF (radio frequency) signal generator defining a component of the first synthesizer forming part of the first transmitter section of the first radar section a chirped local oscillator signal in response to the ramp-like signal generated by the first ramp generator;generating by a first up-converting mixer forming part of the first transmitter section of the first radar section an up-converted mixer signal in response to the chirped local oscillator signal generated by the first RF signal generator and in response to the first phase-shifted frequency offset signal generated by the common multibit phase shifter; generating by a first power amplifier forming part of the first transmitter section of the first radar section an amplified signal in response to the up-converted mixer signal generated by the first up-converting mixer; transmitting by a first transmitting antenna forming part of the first transmitter section of the first radar section a transmit signal in response to the amplified signal generated by the first power amplifier; receiving by a first receiving antenna forming part of the first receiver section of the first radar section a receive signal reflected from an object illuminated by the transmit signal transmitted by the first transmitting antenna and generating a receive antenna output signal in response thereto; generating by a first low noise amplifier forming part of the first receiver section of the first radar section an amplified received signal in response to the receive antenna output signal generated by the first receiving antenna; generating by a first down-converting mixer forming part of the first receiver section of the first radar section an intermediate frequency (IF) signal in response to the amplified received signal generated by the first low noise amplifier and in response to the chirped local oscillator signal generated by the first RF signal generator; generating by a first intermediate frequency (IF) filter forming part of the first receiver section of the first radar section a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the first down-converting mixer; generating by a first analog-to-digital converter forming part of the first radar section a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the first intermediate frequency (IF) filter;generating by a second ramp generator defining a component of a second synthesizer forming part of the second transmitter section of the second radar section a ramp-like signal in response to the clock signal; generating by a second RF (radio frequency) signal generator defining a component of the second synthesizer forming part of the second transmitter section of the second radar section a chirped local oscillator signal in response to the ramp-like signal generated by the second ramp generator; generating by a second up-converting mixer forming part of the second transmitter section of the second radar section an up-converted mixer signal in response to the chirped local oscillator signal generated by the second RF signal generator and in response to the second phase-shifted frequency offset signal generated by the common multibit phase shifter; generating by a second power amplifier forming part of the second transmitter section of the second radar section an amplified signal in response to the up-converted mixer signal generated by the second up-converting mixer; transmitting by a second transmitting antenna forming part of the second transmitter section of the second radar section a transmit signal in response to the amplified signal generated by the second power amplifier; receiving by a second receiving antenna forming part of the second receiver section of the second radar section a receive signal reflected from an object illuminated by the transmit signal transmitted by the second transmitting antenna and generating a receive antenna output signal in response thereto; generating by a second low noise amplifier forming part of the second receiver section of the second radar section an amplified received signal in response to the receive antenna output signal generated by the second receiving antenna; generating by a second down-converting mixer forming part of the second receiver section of the second radar section an intermediate frequency (IF) signal in response to the amplified received signal generated by the second low noise amplifier and in response to the chirped local oscillator signal generated by the second RF signal generator;generating by a second intermediate frequency (IF) filter forming part of the second receiver section of the second radar section a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the second down-converting mixer; generating by a second analog-to-digital converter forming part of the second radar section a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the second intermediate frequency (IF) filter; generating by a third ramp generator defining a component of a third synthesizer forming part of the third transmitter section of the third radar section a ramp-like signal in response to the clock signal; generating by a third RF (radio frequency) signal generator defining a component of the third synthesizer forming part of the third transmitter section of the third radar section a chirped local oscillator signal in response to the ramp-like signal generated by the third ramp generator; generating by a third up-converting mixer forming part of the third transmitter section of the third radar section an up-converted mixer signal in response to the chirped local oscillator signal generated by the third RF signal generator and in response to the third phase-shifted frequency offset signal generated by the common multibit phase shifter; generating by a third power amplifier forming part of the third transmitter section of the third radar section an amplified signal in response to the up-converted mixer signal generated by the third up-converting mixer; transmitting by a third transmitting antenna forming part of the third transmitter section of the third radar section a transmit signal in response to the amplified signal generated by the third power amplifier; receiving by a third receiving antenna forming part of the third receiver section of the third radar section a receive signal reflected from an object illuminated by the transmit signal transmitted by the third transmitting antenna and generating a receive antenna output signal in response thereto;generating by a third low noise amplifier forming part of the third receiver section of the third radar section an amplified received signal in response to the receive antenna output signal generated by the third receiving antenna; generating by a third down-converting mixer forming part of the third receiver section of the third radar section an intermediate frequency (IF) signal in response to the amplified received signal generated by the third low noise amplifier and in response to the chirped local oscillator signal generated by the third RF signal generator; generating by a third intermediate frequency (IF) filter forming part of the third receiver section of the third radar section a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the third down-converting mixer; generating by a third analog-to-digital converter forming part of the third radar section a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the third intermediate frequency (IF) filter; generating by a fourth ramp generator defining a component of a fourth synthesizer forming part of the fourth transmitter section of the fourth radar section a ramp-like signal in response to the clock signal; generating by a fourth RF (radio frequency) signal generator defining a component of the fourth synthesizer forming part of the fourth transmitter section of the fourth radar section a chirped local oscillator signal in response to the ramp-like signal generated by the fourth ramp generator; generating by a fourth up-converting mixer forming part of the fourth transmitter section of the fourth radar section an up-converted mixer signal in response to the chirped local oscillator signal generated by the fourth RF signal generator and in response to the fourth phase- shifted frequency offset signal generated by the common multibit phase shifter; generating by a fourth power amplifier forming part of the fourth transmitter section of the fourth radar section an amplified signal in response to the up-converted mixer signal generated by the fourth up-converting mixer;transmitting by a fourth transmitting antenna forming part of the fourth transmitter section of the fourth radar section a transmit signal in response to the amplified signal generated by the fourth power amplifier; receiving by a fourth receiving antenna forming part of the fourth receiver section of the fourth radar section a receive signal reflected from an object illuminated by the transmit signal transmitted by the fourth transmitting antenna and generating a receive antenna output signal in response thereto; generating by a fourth low noise amplifier forming part of the fourth receiver section of the fourth radar section an amplified received signal in response to the receive antenna output signal generated by the fourth receiving antenna; generating by a fourth down-converting mixer forming part of the fourth receiver section of the fourth radar section an intermediate frequency (IF) signal in response to the amplified received signal generated by the fourth low noise amplifier and in response to the chirped local oscillator signal generated by the fourth RF signal generator; generating by a fourth intermediate frequency (IF) filter forming part of the fourth receiver section of the fourth radar section a filtered intermediate frequency (IF) signal in response to the intermediate frequency (IF) signal generated by the fourth down-converting mixer; generating by a fourth analog-to-digital converter forming part of the fourth radar section a digitized filtered intermediate frequency (IF) signal in response to the filtered intermediate frequency (IF) signal generated by the fourth intermediate frequency (IF) filter; and generating by a radar signal processor forming part of the architecture of the FMCW MIMO radar one or more signals relating to the velocity and range of the object illuminated by the transmit signal of at least one of the first radar section, the second radar section, the third radar section and the fourth radar section in response to the digitized filtered intermediate frequency (IF) signal generated by the first analog-to-digital converter of the first radar section, the digitized filtered intermediate frequency (IF) signal generated by the second analog-to-digital converter of the second radar section, the digitized filtered intermediate frequency (IF) signal generated by the third analog-to-digital converter of the third radar section and the digitizedfiltered intermediate frequency (IF) signal generated by the fourth analog-to-digital converter of the fourth radar section; wherein the chirped local oscillator signal generated by the first RF signal generator of the first synthesizer of the first transmitter section of the first radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the first phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the first radar section, when mixed by the first up-converting mixer of the first radar section with the chirped local oscillator signal generated by the first RF signal generator of the first radar section, causes the up-converted mixer signal generated by the first up-converting mixer to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a known time delay in the receive signal received by the first receiving antenna of the first radar section, the time delay being compensated for in the radar signal processor; wherein the first phase shift of the first phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the first radar section introduces a corresponding phase shift in the receive signal received by the first receiving antenna of the first radar section substantially equal (for lossless reflective objects) to the predetermined first phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; wherein the chirped local oscillator signal generated by the second RF signal generator of the second synthesizer of the second transmitter section of the second radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequencyrange in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the second phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the second radar section, when mixed by the second up- converting mixer of the second radar section with the chirped local oscillator signal generated by the second RF signal generator of the second radar section, causes the up-converted mixer signal generated by the second up-converting mixer to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a time delay in the receive signal received by the second receiving antenna of the second radar section, the time delay being compensated for in the radar signal processor; wherein the second phase shift of the second phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the second radar section introduces a corresponding phase shift in the receive signal received by the second receiving antenna of the second radar section substantially equal (for lossless reflective objects) to the predetermined second phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; and wherein the chirped local oscillator signal generated by the third RF signal generator of the third synthesizer of the third transmitter section of the third radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the third phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the third radar section, when mixed by the third up-converting mixer of the third radar section with the chirped local oscillator signal generated by the third RF signal generator of the third radar section, causes the up-converted mixer signal generated by thethird up-converting mixer to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a time delay in the receive signal received by the third receiving antenna of the third radar section, the time delay being compensated for in the radar signal processor; wherein the third phase shift of the third phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the third radar section introduces a corresponding phase shift in the receive signal received by the third receiving antenna of the third radar section substantially equal (for lossless reflective objects) to the predetermined third phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; wherein the chirped local oscillator signal generated by the fourth RF signal generator of the fourth synthesizer of the fourth transmitter section of the fourth radar section has inherent phase noise associated therewith, the phase noise having a frequency spectrum which includes a peak frequency range in which the phase noise is highest in amplitude and an off-peak frequency range in which the phase noise is lower in amplitude than the amplitude of the phase noise at the peak frequency range; wherein the fourth phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the fourth radar section, when mixed by the fourth up- converting mixer of the fourth radar section with the chirped local oscillator signal generated by the fourth RF signal generator of the fourth radar section, causes the up-converted mixer signal generated by the fourth up-converting mixer to include phase noise that is offset in frequency to the off-peak frequency range by the known and fixed frequency offset; wherein the frequency offset signal generated by the common frequency offset signal generator introduces a time delay in the receive signal received by the fourth receiving antenna of the fourth radar section, the time delay being compensated for in the radar signal processor; wherein the fourth phase shift of the fourth phase-shifted frequency offset signal generated by the common multibit phase shifter and provided to the fourth radar section introduces a corresponding phase shift in the receive signal received by the fourth receivingantenna of the fourth radar section substantially equal (for lossless reflective objects) to the predetermined fourth phase shift caused by the common multibit phase shifter, the corresponding phase shift in the receive signal being determined through matched filtering in the radar signal processor; and wherein the first phase shift of the first phase-shifted frequency offset signal, being orthogonal to the second phase shift of the second phase-shifted frequency offset signal, the second phase shift of the second phase-shifted frequency offset signal, being orthogonal to the third phase shift of the third phase-shifted frequency offset signal, and the third phase shift of the third phase-shifted frequency offset signal, being orthogonal to the fourth phase shift of the fourth phase-shifted frequency offset signal, minimizes cross-correlation between the receive signal received by the first receiving antenna of the first radar section, the receive signal received by the second receiving antenna of the second radar section, the receive signal received by the third receiving antenna of the third radar section and the receive signal received by the fourth receiving antenna of the fourth radar section.

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