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- 저자 : Mkrtchyan, Gagik (검색결과 4 건)
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Mkrtchyan, Gagik,Naito, Katsuhiro,Mori, Kazuo,Kobayashi, Hideo 통신위성우주산업연구회 2005 Joint Conference on Satellite Communications Vol.2005 No.-
In variety of mobile communication applications, there are a lot of necessities for the maximum Doppler spread estimation. As for the multi-path fading channels especially when there is no strong direct path, the Doppler spread estimation would become quite complicated problem. The conventional approach for Doppler spread estimation is usually based on the signal's autocorrelation calculation under the assumption of Jake's propagation model using the inverse of the first order Bessel's function. But this method has several drawbacks: it requires stationary and ergodic data signal, precise Bessel's function inversion and very long correlation time, all of which lead the inaccuracy estimation in the high mobility condition. In this paper we propose a novel Doppler spread estimation method using the time domain estimated channel's impulse response. This paper also demonstrates that the mean square value of time derivative of impulse response divided by the impulse response's mean square value is proportional to the square of the maximum Doppler spread. By using this fact, the proposed method can achieve the accurate estimation of Doppler spread. Computer simulations show that proposed method allows the accurate estimation of the Doppler spread from 10Hz to 1000Hz.
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