Background:

Wireless networks in wide area communication networks have advantage over wired networks as they eliminate the cost of wired infrastructure as well as they can transmit data from harsh environments and locations which can be seldomly accessed by wired networks. However, wide area communication networks with wireless network segments typically have a few major limitations as follows: (1) Their limited and highly variable link bandwidth; (2) Their susceptibility to bandwidth losses due to various kinds of interference; (3) Their reduction in throughput performance due to attenuation of radio signals with distance and performance degradation due to attenuating objects in the signal path; (4) The user of the ubiquitous Transmission Control Protocol (TCP), which is not optimized for use in wireless networks, is another factor that can reduce the available bandwidth of wireless networks. Wide area communication networks with shared network segments can also have variable link bandwidth depending on the network traffic. Although these limitations are okay to go with, the real problem is faced for real-time applications. Usefulness of data decays rapidly in such applications and thus latency here should be managed to avoid stale data. For networks with constrained and variable network bandwidth, the data latency and the required data rate (required throughput) are interrelated. Therefore, neither desired throughput nor latency can be guaranteed.

Summary:

A method and apparatus to continuously transmit high bandwidth, real-time data, on a communications network is described in this patent. The described system enables a control computing device to dynamically adjust the throughput from a remote computing device to match the bandwidth of the communications network being used, so that data latency is minimized and the available network bandwidth is fully utilized. The system allows for the visualization of the instantaneous characteristics of the link and, if necessary, makes a tradeoff between the latency and resolution (throughput) of the data to help maintain the real-time nature of the system.

Automated control strategies are implemented into the system to enable dynamic adjustments of the system throughput to minimize latency while maximizing data resolution. A remote computing device acquires raw data from a multiple of sensors. The resolution of the raw sensor data is adaptively adjusted before the sensor data is transmitted over the communications network to the control computing device. The remote computing device saves the raw sensor data and then adjusts the resolution based on the control commands. Data stream received from multiple sensors are merged into single stream but before that data from each sensor is split into segments whose resolutions are controlled and then passed on to control computing device. On receiving the network sensor data, computing device dynamically measures the network throughput and data latency and displays network characteristics in real-time. It then sends control commands to the remote computing device, based on which the resolution of the network sensor data stream is adjusted. Adjusting of the resolution of the sensor data comprises techniques such as mean reduction, a maximum reduction, a minimum reduction, varying the resolution of the sensor data to an application acceptable minimum, etc. The resolution adjustment is content sensitive.

Benefits:

- Faster transmission of packet data

- Reduced latency and improvement of timeliness in real-time systems

Applications:

- Telecom sector

- MEMS Industry

- Surveillance systems

Full Patent: Method And Apparatus For Adaptive Transmission Of Sensor Data With Latency Controls