A study of received signal-level distribution in wideband transmissions in mobile communications
Jiang Yan, Shigeru Kozono · IEEE Transactions on Vehicular Technology · 1999
A mobile propagation model, which includes not only indirect arriving waves but also a direct arriving waves and is applicable to picocell, microcell, and macrocell, is proposed in order to clarify fundamental propagation characteristics in instantaneous received signal-level variation through narrowband and wideband transmissions. On the basis of this model, we derive a mathematical expression for the instantaneous received signal-level. Through an analysis of this expression, a new propagation parameter called equivalent received bandwidth 2/spl Delta/f/spl Delta/L/sub max/ is proposed. The dependence of the received signal-level distribution on the new parameter is studied by computer simulation. It is shown that the fading depth depends strongly on the 2/spl Delta/f/spl Delta/L/sub max/, as a parameter of the power ratio a. When 2/spl Delta/f/spl Delta/L/sub max/10 MHz/spl middot/m, the fading depth depends not only on the power ratio a but also on the 2/spl Delta/f/spl Delta/L/sub max/ and it decreases as 2/spl Delta/f/spl Delta/L/sub max/ increases. On the other hand, the number of arriving waves and the minimum effective amplitude of arriving waves are examined quantitatively. According to the results, when the number of arriving waves N is larger than 6, the fading depth is independent of N, and the minimum amplitude of arriving waves should be larger than -20 dB relative to the maximum amplitude in indirect arriving waves.