Monostatic radar

Contours of constant signal to noise ratio follow the lines of ovals of Cassini as the signal to noise ratio is inversely proportional to the product of the squares of the transmitter to target and target to receiver ranges. In monostatic radar contours of constant signal to noise ratio are circles. 

There are also some important differences in the technology required to realise bistatic radar. In monostatic radar synchronisation between transmission and reception is done via a stable source, usually a local oscillator. In bistatic radar the separation of transmitter and receiver makes this much more difficult. An equivalent situation has to be achieved and this is done either via synchronised atomic clocks, a signal such as GPS or by reception of a reference signal received directly from the transmitter. The latter technique is typically used in PCL systems and we shall return to this later. 

Another important difference between bistatic and monostatic radar is that a directional receive antenna must scan at a non uniform rate to follow the position of the transmitted signal through space, a process known as pulse chasing. This can be very challenging for designs based upon mechanical scanning and hence an alternative is to use one or more electronically agile beams as in phased array radar. Such phased array antennas can be expensive and in some applications will prohibit the use of the bistatic technique. 

Range resolution is the ability of a radar system to distinguish two closely spaced targets at differing ranges. In monostatic radar this is primarily a function of pulse length or modulation bandwidth. Azimuth... 

Keywords tomography moving targets spatial diversity ultra narrow band (UNB) monostatic radar multistatic radar. 

The monostatic radar received signal power equation representing the signal received at an enemy detection radar, and the received jamming power transmitted toward the same enemy detection radar, are presented in the equations given in Table 17.9. Each quantity in the equations is defined in the table. These... 

In this section we review the fundamental building blocks of bistatic radar emphasising similarities and differences with the more usual monostatic counterpart. Figure 1 shows a typical bistatic geometry with clear separation of the transmitter and receiver. 

Other degrees of freedom that can be varied are the baselines Li. Returning to the geometry of the first example, where Or = —80°, the additional transmitter is placed in the position of the receiver, thus having a combination of monostatic and bistatic radar. In this way topologies can be tailored to meet application needs. However, it is most important to note that this must be balanced against the increased complexity of... 

CONTINUOUS WAVE RADARS-MONOSTATIC, MULTISTATIC AND NETWORK... 

Continuous wave radars-monostatic, multistatic and network... 

The radar antenna, in addition to transmitting and receiving the radar waves, is responsible for the focussing of the millimeter waves. In principle, planar antennas, lens antennas, or reflector antennas can be used. Today, monostatic lens antennas are commonly in use. 

Monostatic antennas use the same focussing mechanism for the transmitted and the received signals, with the signal channels being separated electronically. Direction-sensitive decoupling between the transmitted and the received signals is required for the FMCW radar. As indicated in Fig. 7.7.3, this can be achieved with a circulator or with suitable directional coupler structures. Fig. 7.7.4 is a photograph of the Bosch 77 GHz sensor. 

Fig. 7.7.3 Frequency modulated continuous wave radar with monostatic lens antenna and circulator...

The signal-to-noise ratio (SNR) for a single puke from a monostatic puked radar in free space is given as... 

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