Performance Analysis of Optical-CDMA for Uplink Transmission in Medical Extra-WBANs

Abstract

This paper considers the use of infrared wireless communications for uplink transmission in extra wireless body-area networks. We focus on a multiuser medical application, where the collected medical data of several patients inside a hospital room is transmitted to one or several access points (APs). For this uplink transmission, we investigate the performance of optical code-division multiple access in asynchronous mode, while taking into account the effect of random transmitter orientation. For this purpose and to consider realistic scenarios, we implement an orientation-based random waypoint mobility model to consider the mobility of patients inside a hospital ward. Performance evaluation is done in terms of the link average bit-error-rate and outage probability. We further investigate the performance improvement by using several APs, compared with the case of a single AP. INDEX TERMS Wireless body area networks; Medical WBAN; Telemedicine; Wireless optical communications; Infrared data transmission; Optical code-division multiple access; Random waypoint model; Binary pulse-position modulation.

Performance analysis of optical extra-WBAN links based on realistic user mobility modeling

“…Future work can consider the case of multiple users in a room and the development of efficient multiple-access techniques, as in Ref. 21. Also, to use in large indoor spaces, appropriate multicell architectures need to be designed with the possibility of hand-over, supporting user mobility.…”

Impact of Synchronization Errors on the Performance of ACO-OFDMA Signaling for Medical Extra-WBAN Links

“…As expected, P out increases as the desired user moves from the cell center to the cell edge due to a higher probability of loosing the LOS link. Also, MAI increases with increased d. Note that, for R b = 1 Mbps, the required quality of service P out = 10 −2 [8] is achieved for d ≲ 1.9 m. For increased data-rate, and hence, signal constellation size, synchronization errors show a more penalizing effect.…”

Wireless Body-Area Networks in Medical Applications Using Optical Signal Transmission

“…Nevertheless, efficient multipleaccess (MA) signaling should be used to avoid interference between the (extra-WBAN) signals of different users, as well as between the (intra-WBAN) links of the different SNs. Whereas the optical code-division multiple access (O-CDMA) has been shown to be a suitable MA scheme in the physical (PHY) layer for the case of extra-WBANs [3], managing MA interference in intra-WBAN links is more challenging.…”

“…A WBAN consists of a set of sensor nodes (SN) that are connected to a coordinator node (CN) through intra-WBAN links. The CN then transmits the collected data to a mobile device or a fixed access point (AP) via an extra-WBAN link [2,3]. WBANs have stringent requirements regarding energy consumption and latency, as well as specific characteristics such as the non-stationary nature of the networks due to the movement of the patients, and the heterogeneity of applications [4].…”