CRAWDAD cmu/supermarket

Round-trip Time-of-flight Measurements from a supermarket.The dataset is meant to aid development and evaluation of indoor location in complex indoor environments using round-trip time-of-flight (RToF) and magnetometer measurements. The dataset provides Round-trip time-of-flight (RToF) and magnetometer measurements at 1589 mobile node locations from 30 deployed stationary anchors in the 26m x 24m New Wing Yuan supermarket in Sunnyvale, CA. The data was collected during working hours over a period of 15 days. The nodes are equipped with chirp spread spectrum Nanotron nanoLoc radios (802.15.4a) and a Honeywell's HMC5843, a 3-axis digital magnetometer. At every location, 20 distinct readings were obtained for RToF signatures as well magnetometer measurements, to capture the variance, giving a total of 31780 readings.date/time of measurement start: 2011-02-15date/time of measurement end: 2011-03-01collection environment: The data is collected in the New Wing Yuan supermarket in Sunnyvale, CA, USA (1139 N Lawrence Expy Sunnyvale, CA 94089) during working hours. 30 anchor nodes are deployed over the supermarket. Volunteer students equipped with a mobile sensor node measure the RToF values from the anchors at 1589 distinct locations in the aisles and perimeter of the supermarket. An illustration of the layout, product placements, placement of sensor nodes and point of measurements is included in README.pdf.network configuration: The network consists of 30 deployed anchor nodes equipped with 802.15.4a Nanotron nanoLoc transceivers. A mobile node also equipped with a 802.15.4a Nanotron nanoLoc transceiver attempts to obtain RToF measurement from all anchors in a single-hop network configuration.data collection methodology: The network consists of 30 deployed anchor nodes (15 at a time) equipped with 802.15.4a Nanotron nanoLoc transceivers. The supermarket is split into two parts and 15 nodes are deployed at a time. A mobile node also equipped with a 802.15.4a Nanotron nanoLoc transceiver polls all 15 deployed anchors on command, over an interval of 30 seconds, waiting 1 second to obtain an RToF measurement from each anchor. 3 retries are attempted in every 1-second slot. The mobile node is attached to a stick and mounted at height of 1.5m from the ground to maintain a constant vertical position. The orientation of the node is always held constant facing the north wall of the supermarket. In addition, a magnetometer reading is recorded at each location. 20 sets of readings are recorded at each location. The RToF and magnetometer measurements are logged as a text file on a workstation attached to the mobile node with timestamps.limitation: The data at each location is obtained over a period of 20 minutes, covering the entire supermarket area over a period of 15 days. As readings are not obtained simultaneously, the methodology incorporated diurnal variations in measurements. Tracesetsupermarket_rtofRToF and Magnetometer measurements over a supermarketsupermkt_rtof_trace file: cmu_supermarket.csv.gzconfiguration: The network consists of 30 deployed anchor nodes (15 at a time) equipped with 802.15.4a Nanotron nanoLoc transceivers. The supermarket is split into two parts and 15 nodes are deployed at a time. A mobile node also equipped with a 802.15.4a Nanotron nanoLoc transceiver polls all 15 deployed anchors on command, over an interval of 30 seconds, waiting 1 second to obtain an RToF measurement from each anchor. 3 retries are attempted in every 1-second slot. The mobile node is attached to a stick and mounted at height of 1.5m from the ground to maintain a constant vertical position. The orientation of the node is always held constant facing the north wall of the supermarket. In addition, a magnetometer reading is recorded at each location. 20 sets of readings are recorded at each location. The RToF and magnetometer measurements are logged as a text file on a workstation attached to the mobile node with timestamps.format: Comma-separated Matlab data columns: x,y,z,magnetometer reading, 30 RToF readings from anchors NaN = no values available or timeout/out of range