MIMO detection: Myth or Reality?
MIMO detection: Myth or Reality?
09 Novembre 2011 - 10 Novembre 2011
09/11/2011 23:00 - 10/11/2011 16:00
The French SEE’s (Société des Electriciens et Electroniciens) Technical Committee SRSR (Systèmes Radar Sonar et Radioelectriques) , in charge of activities in the domains of detection, localization and navigation, in co-operation with the IEEE-AESS French Chapter, is planning a one-day seminar on the MIMO techniques for radar, passive detection and sonar applications.
 
Under this acronym, the MIMO concepts were first introduced in wireless communications field with two main goals:
  • To increase the data-rate throughput with same power / bandwidth;
  • Robustness to fading due to multiple paths, even take benefit of multiple paths.
At the beginning of the new millennium, the Radar community has elaborated on this concept in two variants, which may be combined together:
  • The “coherent MIMO” where the transmission and reception antennas are co-located. The word “coherent” means that the extent of the array is smaller than the diffraction lobe of the target, so that coherent spatial integration can be performed. The co-location of the transmission and reception antennas clusters is generally a sufficient condition to fulfill this.
  • The “statistical MIMO” were the antennas are spread over wider areas, and may operate on transmission, reception, or both. Unlike the previous case, this configuration allows spatial diversity.
  • For short range applications (eg imaging), use of sparse arrays, generally combined with Ultra-Wide Band signals optimisation of the point spread function of the sensor.
The practical use of these concepts is now enabled by the emergence of active array antennas. Indeed, an active array antenna is no longer a component whose characteristics are fixed at the design stage but may be arranged in multiple sub-apertures, separately configurable. For example, it can be used
to transmit simultaneously multiple waveforms in different directions.
These concepts have been shown to be applicable in sonar as well, and medical imaging is another possible
application area.
On the borders of MIMO systems, the availability of broadband communications, global positioning and ultra-precise time references enables the networking of sensors, whether active or passive.