In this paper, an extensive set of propagation path loss measurements within multi-floored buildings at
433 MHz, 869 MHz and 1249 MHz are presented. Parameter for use in two indoor path loss prediction
models, Distance-Dependant Model (DD) and Floor Attenuation Floor Model (FAF), are derived from
measurement data of three multi-floored buildings. Buildings were chosen with typical features such as
rectangle footprint, square footprint and existence of an atrium within the building, respectively.
Comparison of model parameters has concluded that higher attenuation is experienced by the signal
within a square footprint building than rectangle footprint. Building with an indoor atrium is found to
have lower path losses than buildings without atrium, when considering multi-floor transmission. 869 MHz
signal attenuated at slowest rate in most of the considered environments. 433 MHz signal is found to have
better floor penetration compared to other frequencies. 1249 MHz is found to attenuate at slowest rate
within a straight corridor with waveguiding and line-of-sight propagation path between the transmitter and
Path loss prediction within multi-floored buildings with indoor atrium is refined by considering type of
propagation path between trnamsitter and receiver. It is found that path loss of areas with line-of-sight
propagation path could be modelled using parameters of same floor environment. An attenuation factor is
derived and added for areas with non line-of-sight propagation path. It is shown that using this refinement,
better prediction accuracy is obtained. Standard deviations of path loss prediction error are reduced as a
In this paper, parameter statistics of path loss prediction models are presented for 1.25 GHz within multifloored
buildings. Parameters are extracted from analyzed data which was collected from measurements
within three buildings. Buildings were chosen with specific considerations such as building footprint shapes
and internal design.For the consideration of building footprint, a building having rectangular footprint and
a building having square footprint were chosen. Because of its internal design, the third building was chosen
to represent buildings with an atrium. Results show that, buildings with square footprint caused higher
path loss compared to rectangular footprint buildings. It is also found that, buildings with an atrium have
the lowest path loss exponent and lowest floor attenuation factor among other considered buildings.
A model for path loss prediction is proposed for multifloor buildings with its internal design allows lineof-
sight (LOS) and non line-of-sight (NLOS), even though transmitter and receiver are not on the same
floor. The model takes into consideration the factor of transmission type, whether it is LOS or NLOS. The
proposed model has reduced the standard deviation of error prediction, which indicates better prediction
accuracy is achieved.
The paper discusses the limits of error correction coding for spread spectrum-based video watermarking. The error correction code has as input the watermark data bits and as output the values which will be scaled and used to modify the video pixels (transform coefficients). The data rate of the watermark can increase only at the expense of increasing code rate. Theoretically, the scheme is seen as a communication channel with Gaussian additive noise interference.
Shannon's (ideal) spherical codes are used as the error correcting code to calculate the minimum signal to noise ratio (SNR) necessary for a coding scheme with a given block length to achieve a given error probability. This limit is different from Shannon's asymptotic limit, which is valid for infinite block lengths and zero error probability. In practice, in order to verify the Gaussian channel assumption, the error correction code is a concatenation of codes, of which the innermost is a repetition code. Several practical codes of different length and rates, such as turbo codes and BCH codes are investigated and their performance compared to that of the ideal code of the same size. The compromise block length/code rate is investigated for several marking schemes and attacks.