How to estimate the diversiy order?

[James K.]

How to estimate the diversiy order from SNR?
Then, how to estimate the diversiy order from Capacity?

If I do it like below, am I right?

- From SNR, D ~= E[SNR]^2 / Var[SNR],

where, SNR is the signal to noise power ratio, D is the diversiy
order and E[.] is the expectation operator, Var[.] is the operator
estimating the variance of the input variable. This follows the fact
that in D oder diversity channel, which is represented
by e.g. 2D-chi square distribution,

E[SNR] = D*SNR^2,
Var[SNR] = D*SNR^4.

- From Capacity, D ~= m_SNR^2 / var_SNR

where

m_SNR = E[2^C - 1],
var_SNR = Var[2^C - 1],

since C = Log2(1+SNR).

Thank you in advance.
--
BR,
------
James K. ([email protected])
- Any remarks, proposal and/or indicator would be greatly respected.
- Private opinions: These are not the opinions from my affiliation.
[Home] http://home.naver.com/txdiversity

[James K.]

"James K." <[email protected]> wrote in message news:[email protected]...

> How to estimate the diversity order from SNR?
> - From SNR, D ~= E[SNR]^2 / Var[SNR],
> E[SNR] = D*SNR^2,
> Var[SNR] = D*SNR^4.

This method seems very relevant to any kind of diversity methods, e.g. MRC (Maximal Ratio Combine), EGC (Equal Gain Combine), also SEL (Selection diversity), since it is considering to move out the effect of SNR gain, which is different in each diversity method, from the calculation of the diversity order.

The above equations can be re-expressed with considering moving out of the SNR gain as follows

D(g) = E[SNR(g)]^2 / Var[SNR(g)] ¡æ D,
where E[SNR(g)] = D*(g*SNR)^2, Var[SNR(g)] = D*(g*SNR)^4,
and g is the SNR gain for each method.

Thus, there is no impact from SNR gain when we calculate the diversity gain by this method.

Thank you in advance.
--
BR,
------
James K. ([email protected])
- Any remarks, proposal and/or indicator would be greatly respected.
- Private opinions: These are not the opinions from my affiliation.
[Home] http://home.naver.com/txdiversity