Spectrum is a limited and valuable resource. The escalating requirement for wireless communication and broadband services has augmented the attempts to improve the designs for wireless systems. These enhanced wireless systems offer substantial increase in data throughput and link range without the requirement of any additional bandwidth. This led to the development of MIMO Systems. In Multiple-Input Multiple-Output (MIMO) technology, multiple antennas are used at both the transmitter and receiver to improve the functioning of the wireless communication system. We accomplish this objective by exploiting the spatial domain of the transmission medium.
In this chapter, we describe the MIMO system model along with a brief discussion of its…show more content… The detector then chooses one of the BM possible transmitted symbol vectors based on the available data. An optimal detector should return as x ̂ = x*.
3.3 MIMO System Model
The capacity of Single-Input Single-Output (SISO) wireless communication systems must be increased to fulfill the ever-growing demands of efficient transmission rate. This can be done by allocating additional bandwidth which is not always feasible due to the limited spectral resources [Alamouti 1998]. Recent studies have proved that using spatial multiplexing MIMO systems can boost the capacity of a wireless communication system significantly without the prerequisite of extra-bandwidth.
Multipath propagation is an essential component of all wireless communication system. Conventional radio systems rely on the strong primary signal and also make use of multipath mitigation techniques to overcome multipath propagation and interference. Beam forming technology or smart antenna technology is used for this purpose. A smart antenna is capable of routing transmitted beam by scheming the phase of the signal at each element of the antenna array to the receiver. Receiving diversity, this uses numerous antennas at the receiver side and merges all the received signals to improve the signal reliability. These techniques are used to reduce the effect of multipath propagation on the communication systems. MIMO makes use of multipath propagation to get better throughput, range and reliability [Berrou 1996]. In