34 results about "Exponential backoff" patented technology

The invention discloses an automatic equipment identification and maintenance supported DMX512 (Digital Multiplex 512) landscape lighting control system and method. The system consists of a remote control center and a DMX512 control network, wherein the DMX512 control network is downwards compatible with standard DMX512 products occupying the market dominant position; a corresponding slave controller reports equipment identification information when DMX512 equipment is networked for the first time, and a master controller automatically allocates a physical address to the equipment by a physical address allocation algorithm, thus manual operation is avoided; the slave controller prevents from reporting conflicts by adopting a carrier sense and binary exponential backoff algorithm; by virtue of an automatically created equipment list, the master controller detects the status of the equipment regularly, reports the status of the equipment in the DMX512 control network to the remote control center and automatically updates the equipment list; and operating personnel can also manually add new equipment and remove the original equipment as required or modify the physical address of the equipment.

A method for transmitting data from a sender node to a receiver node in a wireless network including (a) sampling a main network frequency and at least one backup frequency, (b) transmitting a message on the main network frequency without using a multiple access protocol, (c) transmitting the message on the main network frequency, using the multiple access protocol exchange, if an acknowledgement is not received, (d) transmitting the message on at least one backup frequency, using a multiple access protocol, if the main network frequency is busy after (c), (e) repeating (c) and (d) for a predefined number of time slots, until an acknowledgement is received, (f) transmitting the message on each backup frequency, using the multiple access protocol, until an acknowledgment is received, and (g) performing an exponential backoff and subsequent transmission of the message if an acknowledgement is still not received after (a) through (f).

Low temperature drift high power supply rejection ratio bandgap reference circuit based on exponential compensation, including pre-regulation module, pre-regulation start-up module, bandgap reference core module and bandgap reference core start-up module, the bandgap reference core module is used to generate reference voltage , the fifteenth PMOS tube with common source connection forms a βhelp structure, which avoids the problem of too small a value of β in the CMOS process, which causes excessive errors in the base current; at the same time, the high-order curvature of the reference voltage is compensated by the ninth resistor R9 The structure is embedded in the βhelp structure, which significantly reduces the temperature drift coefficient of the reference output voltage; the bandgap reference core startup module is used to make the bandgap reference core module break away from the degeneracy point; the pre-regulator module is used to generate a bandgap reference core module The local voltage supplied by the bandgap reference core start-up module, through the self-adaptive drive structure, not only ensures the driving capability of the pre-regulation structure but also effectively improves the power supply rejection ratio of the reference output voltage; the pre-regulation start-up module is used to make the pre-stabilization The compression module leaves the degeneracy point.

The invention relates to a carrier sense multiple access (CSMA) / conditional access (CA) mechanism optimization method in a new institute of electrical and electronics engineers (IEEE)802.15.4 standard. An analysis stage, a determination stage and an execution stage are involved. An initial value of macMinBE in the CSMA / CA is retained, but the backoff index macMinBE is dynamically adjusted according to contention network flow of each node in a certain number of beacon frame intervals, so that a proper backoff range can be dynamically selected by a sensor node according to the condition of a network. Due to optimization, macMinBE can reflect the current network condition accurately, and network use rights among the nodes are balanced. Therefore, the network justice of the nodes is improved, the network throughput is increased, and the network load is reduced. A simulation result shows that: compared with the conventional binary exponential backoff (BEB) algorithm in the IEEE802.15.4, the optimization method for a BEB algorithm with adaptive adjustment capacity has the advantage that under the condition that the network input service amount is relatively large, the network throughput is increased obviously, and the network working load is reduced.