Mobility Diversity-Assisted Wireless Communication for Mobile Robots

Abstract

Abstract-Mobile robots, that wish to communicate wirelessly, often suffer from fading channels. They need to devise an energy efficient strategy to search for a high channel gain position in a near vicinity from which to begin communications. Such a strategy has recently been introduced through the Mobility Diversity with Multi-Threshold Algorithm (MDMTA). In this paper, we establish the theoretical framework for a generalized version of the MDMTA. This allows improved wireless communications in fading channels for mobile robots via intelligent robotic motion with low mechanical energy expenditure.

Mobile Robot Path Planners With Memory for Mobility Diversity Algorithms

“…Nevertheless, it has been shown that we can by controlling the position of the robot we can compensate small-scale fading [17]- [?]. This class of techniques have been referred to as mobility diversity algorithms [21], spatial diversity [15], jittery movements [19] among other names. In this article we will refer to this class of techniques as mobility diversity algorithms (MDAs).…”

“…That configuration for the explored points provides five statistically independent wireless channels. Finally in [21] we presented a technique to calculate the optimum position of the points in order to maximize the expected value of the channel channel gain obtained while minimizing the amount of mechanical energy used in motion during the MDA execution.…”

“…In [15]- [21] the authors propose different configurations for the points explored by the robot in order to compensate for the small-scale fading but another variant to this problem is the one considered in [23] and [24]- [27] where the authors consider that the mobile robot must follow a predefined path while communicating with a base station through an RF wireless channel experiencing small-scale fading. In this case, as opposed to [15]- [21], in order to compensate the small-scale fading the authors do not focus on determining the location of the points where the robot transmits but rather on determining its velocity profile.…”

“…In this case, as opposed to [15]- [21], in order to compensate the small-scale fading the authors do not focus on determining the location of the points where the robot transmits but rather on determining its velocity profile. The solution in those articles is roughly based on the idea of following the predetermined path but spending more time at points (in the predefined path) with high channel gain (due to constructive interference generated by the small-scale fading) and less time at points (in the predefined path) with poor channel gain (due to destructive interference generated by the small-scale fading).…”

“…In this current article we will focus on the variant of the problem considered in [15]- [21]. Thus the main problem considered in this article is to optimally determine the location of the points explored by the robot, in its close vicinity, in order to compensate for the small-scale fading.…”