Reciprocity Approach According to the principle of reciprocity, the forward and reverse channels are identical when the time, frequency, and antenna locations are the same. Based on this principle, the transmitter may use the CSI obtained by the reverse link for the forward link. In practice, the forward and reverse channels are not truly identical because of the effect of channel fading, noises, and environments.
Download 5MB Abstract Recent evolutions in wireless mobile communications have shown that by employing multiple inputs and multiple outputs MIMO technology at both the transmitter and receiver, both the wireless system capacity and reliability can be enhanced without the need for increasing the power transmitted or using more spectrum.
Despite a considerable amount of research have been done on the design of MIMO and diversity handset antennas, the design of low profile, small footprint and multi-standard wideband or multiband diversity antennas on handset devices remains a challenging issue. Therefore, the purpose of this thesis is to present new antenna structures for handset MIMO and diversity applications.
As the MIMO antenna design can be conducted either using multiple element antennas MEA or isolated mode antenna technology IMATthe work in this thesis is fallen in these two general design themes areas. The first area under investigation concerns multiport antennas IMAT antennas.
It has the following two contributions: The isolation between feeds is achieved by two back to back L-shaped ground plane strips. A prototype is made and the optimised diversity parameters are obtained, the results show that this design has a good diversity performance over the frequency range of 2.
|Newcastle University eTheses: MIMO antenna systems for next generation wireless communications||The combination of multiple-input-multiple-output MIMO and orthogonal frequency division multiplexing OFDM techniques have been adopted in recent wireless standards, such as|
It has a wideband response over the frequency range of 2. The design is based on a comparative study on the mutual coupling between different feed arrangements. As a result, the coplanar feed is employed in the proposed antenna; the polarization diversity is achieved by exciting two orthogonal radiation modes.
The isolation between the feeds is achieved by an L-shaped ground plane slot.
Both simulated and measured results demonstrate that the design is a very good candidate for mobile diversity and MIMO applications. The second investigation area concerns multiple element antenna MEA systems for wideband and multiband handset applications.
It includes the following contributions: The antenna isolation is achieved using a parasitic decoupling element inserted between the two elements. A novel approach for the design of the parasitic decoupling element is proposed. It is based on stepped impedance resonator circuit theory.
All the prototypes are made and evaluated; the results show excellent diversity performance over the applications in the frequency range of 1. It consists of two elements: The isolation is achieved due to the resulted orthogonal radiation patterns, especially, at 0.The antennas for 2 £ 2 MIMO are located at ` = 0– and ` = – where as PIERS O NLINE, V OL.
4, N O. 1, for 3 £ 3 MIMO at ` = 0 –, – and –. Precoding and Massive MIMO 1.
Introduction I Unfortunately, due to various problems, the number of antenna elements in an array for downlink beamforming is limited. I However, in 5G, transmit (or downlink) beamforming has been considered seriously to extend the coverage.
Multiple-Input Multiple-Output (MIMO) antenna systems are a form of spatial diversity. In a multipath-rich wireless channel, deploying multiple antennas, at both the transmitter and receiver, achieves high data rate without increasing the total transmission power or.
Argos is an ongoing project developing and optimizing many-antenna MU-MIMO, or Massive MIMO at large scale, systems for real world deployments. antenna array that is compatible with MIMO systems and able to operate on multiple frequencies .
This thesis o ers one possible solution to this problem by presenting a compact. p urpose of this thesis is to give a brief look into multiple antenna techniques with the main focus on MIMO (Multiple -Input Multiple -Output). Basic principles of .