Beijing, China
Beijing, China

Time filter

Source Type

Lu C.,Beijing Zoweetech Ltd | Yan Y.,China Flight Test Establishment | Song J.,Beijing Zoweetech Ltd
Proceedings of the International Telemetering Conference | Year: 2013

High speed real-time data transportation is most important for telemetry systems, especially for large-scale distributed systems. This paper introduces a STDM (Sync Time Division Multiplexing) network structure for data transportation between devices in telemetry systems. The data in these systems is transported through virtual channels between devices. In addition, a proper frame format is designed based on PCM format to meet the needs of synchronization and real-time transportation in large-scale distributed telemetry systems.


Wang Z.,China Flight Test Establishment | Qi S.,China Flight Test Establishment | Song J.,Beijing Zoweetech Ltd | Wang H.,Beijing Zoweetech Ltd
Proceedings of the International Telemetering Conference | Year: 2015

To use Ethernet is the most convenient way to set up a transportation network for a telemetry data acquirement system. However, due to its CSMA/CD (Carrier Sense Multiple Access and Collision Detection) mechanics, Ethernet cannot transport data synchronously. This paper analyzed important features of transportation in a distributed data acquirement system, and presents a resolve for synchronously transporting data in a distributed data acquirement system by using direct Ethernet connection and TDM (time division multiplexing) technique.


Song J.,Beijing Zoweetech Ltd | Luo N.,Beijing Zoweetech Ltd | Cao L.,Beijing Zoweetech Ltd | Xu M.,Beijing Zoweetech Ltd
Proceedings of the International Telemetering Conference | Year: 2015

Power supply is the most critical unit in an airplane. A defect in a power supply might lead to a crash. Therefore, it is very useful and important to monitor the status of the airplane's power supply during flight. This paper presents a real-time evaluation system constructed by a central process unit for processing and detecting defects and several remote units for acquiring parameters. Because of the huge amount of data acquired, a combination of Ethernet and time division multiplexing technique has been applied for constructing a 2.5Gbps synchronous data transportation network for the system.


Lu C.,Beijing Zoweetech Ltd | Kung C.,Beijing Zoweetech Ltd | Song J.,Beijing Zoweetech Ltd
Proceedings of the International Telemetering Conference | Year: 2013

Instead of using a single data acquisition device, the distribute data acquisition system is broadly applied for onboard flight testing now. Therefore, the sync of data acquisition in varied devices and the real time data transportation have become the most important factors in a telemetry system. This paper presents a new approach to clock synchronization in a real time transportation network for a data acquisition system by using IRIG time code and an inner timer through network time recovery technique. This paper also illustrates how to keep the synchronization and continuity of a time tag used by each device through a precise estimation method for the difference of time resources and local inner timers.


Lu C.,Beijing Zoweetech Ltd. | Song J.,Beijing Zoweetech Ltd.
Proceedings of the International Telemetering Conference | Year: 2014

This paper analyzed protocols may be used in each layer in networked telemetry systems, and also presents some deeper researches of the advantages of using synchronous time-division for the physical layer of a networked telemetry system.


Song J.,Beijing Zoweetech Ltd. | Luo N.,Beijing Zoweetech Ltd.
Proceedings of the International Telemetering Conference | Year: 2014

Airborne videos are crucial for monitoring unmanned aircraft systems (UAS). However, the number of videos that could be sent to ground is limited due to the bandwidth of a telemetry system. An architecture of airborne video acquirement system with real-time management is present in this paper. In addition to acquire videos and other data like control commands, that architecture make it possible to manage and switch the videos to be transferred to the ground through telemetry channels for ground real-time monitoring and controlling.

Loading Beijing Zoweetech Ltd collaborators
Loading Beijing Zoweetech Ltd collaborators