21-03-2011, 12:16 PM
Presented by:
K.V.Hareesh
G.Venkata Rao
M.Karthik
J.Srikanth
A.Kalyan Joshi
haeesh40.pptx (Size: 239.66 KB / Downloads: 41)
ABSTRACT
UHF TV channels are traditionally used for television broadcasting where the channels can be regarded static or slowly-varying.
In this paper, new results on the temporal and spatial characteristics of the wideband UHF mo-bile wireless signals and channels in the Digital Television (DTV) broadcasting UHF frequency bands are presented.
Our analysis of DTV mobile field measurements confirms that the complex channel correlation amplitude depends on the channel phase correlation and differs considerably from the channel envelope correlation
INTRODUCTION
THE UHF spectrum, which ranges from 300 MHz to 3 GHz, is densely allocated to communications applications, such as TV broadcasting, radio astronomy, public safety and wireless networks. Traditionally the UHF DTV channels are static or slowly varying with one transmit antenna located on top of a high tower and one receive antenna located at the residential or mid-height building level
In this paper, we investigated the joint statistics of the wideband mobile wireless downlink and uplink channels in the UHF TV bands.
Block Diagram
Joint Wireless Channel and Signal Statistics
In this paper, we investigated the wireless channel joint statistics as well as the received signal joint statistics.
The joint channel statistics under study are the channel correlation function
Wireless Channel Model And Channel And Recived Signal Joint Statistics
In a MIMO (multiple input - multiple output) system, multiple transmit antennas and multiple receive antennas are installed at the transmitter and the receiver, respectively. The timevarying MIMO channel can be represented in matrix form
The definitions of the correlation coefficients are summarized in Table I while the definition of the channel correlation function follows:
The contributions of this paper are three-fold and are important to the design of new wireless systems, which will be deployed in the vacant UHF frequency bands in the near future.
A) First, the measurement results confirm that, the complex channel correlation
B) Second, in our measurements, the transmit DTV ATSC signal autocorrelation degrades the received signal amplitude correlation coefficients, , in comparison with the channel envelope correlation coefficients
c) Third, from the obtained numerical results, we found that the channel envelopes are relatively highly correlated while the channel phases are uncorrelated.
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