Presentation on theme: "Survey on body area network 姜升. Structure BAN Sensor devices Communication technology PHY Network and MAC Energy Application."— Presentation transcript:
Survey on body area network 姜升
Structure BAN Sensor devices Communication technology PHY Network and MAC Energy Application
BAN A body area network (BAN) is a wireless network of wearable computing devices. The network consists of several miniaturized body sensor units together with a single body central unit.
BAN Deployment Data rate Mobility BANWSN DeploymentBAN does not employ redundant nodes, and only added when they are needed. WSN is often deployed in places that may not be easily accessible by operators which require more nodes to be placed to compensate for node failures. Data rateBAN may occur in a more periodic manner and stable data rate. Most WSNs are employed for event-based monitoring where events can happen at irregular intervals. MobilityBAN users may move around, so that the nodes share the same mobility pattern. WSN nodes are usually considered stationary.
Sensor devices Inertial motion unit (Accelerometer and Gyroscope) Blood glucose Blood pressure CO 2 gas sensor Electrocardiogram (ECG) Electroencephalogram (EEG) Blood oxygen Electromyography (EMG) Humidity and temperature sensors
Communication technology TechnologyFrequency band Data rate (b/s)Coverage distance Network topology UWB3.1~10.6GHz480M<10star Zigbee2.4GHz250K30~100Star/mesh Bluetooth2.4GHz1M10star UWB (Ultra wideband) Zigbee Bluetooth
PHY Studies focus on characteristics of the signal propagation: around the body (LOS/NLOS)/inside the body Factors affecting the signal propagation – Location of the BAN user – Location of the sensor node – Current activity of the human body
PHY Measurement – Radio signals are generated in the network analyzer, input in the body through the TX, received in the RX and evaluated in the network analyzer.
PHY Characteristics of signal propagation LOS – It is found that the increase of distance between TX and RX causes an increase of the path loss – The dominant propagation path is the direct wave – In classroom, the power of reflected waves exceeded that of the direct wave for the lower body NLOS – The propagation wave is more likely to diffract around the human body rather than to pass through it – The dominant path is reflected wave in classroom is reflected wave.
PHY – The difference between body shapes (i.e. male, female and child) are at least as large as the impact of a patient's arm movements. In the body – Signals propagating in the body are attenuated mainly due to absorption of power in the tissue. The path loss is much higher than the free space propagation. – the frequency bands between 200MHz to 600MHz are suitable in the range from 0 to 3GHz. – In frequency range of 3-11 GHz, The signal attenuation in the body increases when the frequency increases. Human body has a good response to signal transportation in the bands between 3-5 GHz.
Network and MAC Network – DTN routing/probabilistic routing
Network and MAC Scheduling based MACContention basted MAC Power consumptionLowhigh Bandwidth utilizationMaximumlow Transmission efficiencyHighlow MAC – Scheduling based – Contention based
Network and MAC MAC – Most current MAC protocols specifically developed for BAN are based on IEEE , as most of the radios used in WBANs are based on IEEE compliant chip set.
Energy Energy consumption – Sensing – Communication – Data processing Approach – Turn on/off the radio periodically – Reducing idle listening/contention/overhearing
Energy MAC Network topology Approach BSN- MAC TDMA/CS MA mixed Star topology The coordinator utilizing the priority of the nodes to make adjustment H-MAC TDMA based Star topology Exploiting heartbeat rhythm information to perform time synchronization CICADA TDMA based Tree topology Setting up a network tree for data gathering and communication using distributed slot assignment Omeni TDMA based Star topology Using master-slave approach and assigning an extra slot to the node for direct communication at alarming time
Energy ProtocolNetwork topologyApproach AnybodyMeshUsing clustering to reduce the number of direct transmissions to the remote base station
Training Health monitoring Positioning – Particle filtering/Kalman filtering/range free/ML/LS/DV-hop ApplicationScenarioFeedback TrainingDance/golf/swimming/football/p hysical rehabilitation Guidance Health monitoring Remote health monitoring/falling detection Physical information and alarming PositioningLocation