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Figure 7. (a) Comparison between the actual base-of-support distance and BOS measurement error of
commercial system via simulation. and (b) Comparison between the actual BOS distance and measure-
ment error of the proposed system via simulation (Shaban 2010; Shaban, El-Nasr et al. 2010) ©2010
IEEE. Reprinted, with permission, from Shaban et al., “Toward a Highly Accurate Ambulatory System
for Clinical Gait Analysis via UWB Radios”, in IEEE publication title: IEEE Transactions on informa-
tion technology in Biomedicine, vol. 14, NO. 2, Mar. 2010.
been studied. Furthermore, important factors
that affect performance, such as synchronization
errors have been addressed. Moreover, actual
measurements have been provided for the verifi-
cation of the proposed system. Additionally, the
integration of UWB sensors with other sensors
has been investigated.
In our link budget, we showed that the link-
margin is expected to be equal to 10 dB at the
target 1 mm ranging accuracy. The 10 dB link-
margin was calculated w.r.t. the 18 dB SNR re-
quirement based on the ZZLB. We also showed
that the proposed system initialization requires
20.14 seconds for a complete setup. The localiza-
tion technique used at the system initialization
stage was the linear-LS (as it is a low-complexi-
ty solution that could provide us with the required
high positioning accuracy), and was shown to
achieve an average positioning accuracy equal to
0.247 mm. The core measurement phase was also
studied. At that stage, we assumed using C-MDS
localization approach preceded by an FFT inter-
polation. The achieved accuracy of acquired data
during this stage was shown to be 0.47 mm ±
52 µm. Results were obtained via simulations in
the IEEE 802.15.6a channel based on actual ac-
quired MoCap data. This chapter also investi-
gated the node arrangement, and proposed group-
ing the nodes in LOS links guaranteed regions
that guarantee LOS links during movement.
Theoretical and simulation results were further
justified via actual measurements taken at the
MPRG labs for the verification of the provided
measurement accuracy by our proposed system.
Results showed that the proposed system is capable
of providing a 1 mm ranging accuracy using an
optimal template at an SNR = 20 dB and 22 dB
using a suboptimal real sinusoidal template.
Sensor-fusion was also investigated, and
the overall system performance was evaluated.
Specifically, we studied the integration of UWB
sensors with foot force sensors for the evaluation
of gait kinetics. Then, we studied and compared
the accuracy provided by our proposed system
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