What is array gain in MIMO?
Array gain is defined as the increase in SNR in MIMO systems compared with that of SISO systems. It is a result of coherent combining of multiple signals, either from multiple transmitters or from multiple receivers.
What is the meaning of array factor?
The array factor is the complex-valued far-field radiation pattern obtained for an array of isotropic radiators located at coordinates , as determined by: where are the complex-valued excitation coefficients, and is the direction unit vector.
What is meant by gain of antenna array?
The antenna array gain is defined as the ratio of the intensity in a given direction to the radiation intensity that would be obtained if the same power is radiated using a single isotropic radiator.
What is K in array factor?
In addition, if the array is transmitting, the radiation pattern will be identical in shape to the receive pattern, due to reciprocity. Y can be written as: where k is the wave vector of the incident wave. The above equation can be factor simply as: The quantity AF is the Array Factor.
What is Array gain and diversity gain?
The difference between array gain and diversity gain is that array gain gives an increase in the average SNR, while diversity gain makes the probability density function of the instantaneous SNR more concentrated around its average value.
What does array factor depend on?
Array analysis: to obtain array factor (AF) given array configuration and element feedings. Array synthesis: To determine the array configuration and/or element feedings to achieve desired array factor. It depends on: (1) the relative location of the elements (2) the relative excitation of the elements.
What is directivity and gain?
Directivity specifies the concentration of radiated power in a particular direction. Gain specifies the concentration or fraction of input power (includes total of radiated power and dissipated power as ohmic losses) in a particular direction.
How is diversity gain calculated?
In order to find the diversity gain, the power samples of the two branches are combined by selection combining (SC) and maximal ratio combining (MRC) [12]. With SC the branch with the highest power for each of the 3750 equal measurement situations is always selected.
Is there a correction factor for power gain in antenna arrays?
In this short paper, we present a power correction factor for common definitions of power gain of antenna arrays that allows them to be used in standard link budget calculations. Ramakrishnaiah, V. , Kubichek, R. and Muknahallipatna, S. (2018) Correction Factor for Power Gain in Antenna Arrays.
How is the array factor and element factor related?
The array factor consists of orientation and separation information of point sources while the element factor gives the radiation characteristic of given antenna element. The antenna radiation pattern can be calculated by multiplying the array factor with the element factor of given antenna.
What is the gain of a horizontal array?
Both a vertical array (8×1) and a horizontal array (1×8) offer 10log 108 ≈ 9 dB gain as compared to the single element. For the horizontal array (1×8) the main lobe is narrow in the horizontal plane, but as wide as the single element in the vertical plane.
How is the array factor factored in beam steering?
To sum up, for basic beam steering with a UPA, the array factor can be factored into an array factor for a horizontal array and an array factor for a vertical array. The gain as compared to a single element is still given by the total number of elements.