IEEE Std 802.15.4s pdf free download

IEEE Std 802.15.4s pdf free download.Low-Rate Wireless Networks Amendment 6: Enabling Spectrum Resource Measurement Capability.
SRM enables devices to gather a variety of data for evaluating radio link performance, which contributes to the selection of the best available PAN for joining and efficient radio spectrum usage for the selected PAN. As shown in Figure 5-10, the device obtains radio link characteristics by local measurements or via exchange of information with other devices via reporting messages all the way to the PAN coordinator. The PAN coordinator is also able to disseminate information to the devices in the PAN, such as the maximum transmit power, by which the receiving devices can set their radio parameters in a unified manner. SRM data is also made available to the upper protocol layers, which is able to use it for controlling the lower layer or their applications.
The measurement of SRM metrics are conducted only when the device is capable of doing it. In the case of LE transmission and reception, for example, even if the requesting device requests the peer device to measure SRM metrics for a specific duration of time. the requested device can do it only when the receiver is enabled.
In the case of TSCH. there are three modes of measurement operation.
Full measurement: the device conducts the measurement for a specified duration of time regardless of the channel.
Channel-specific measurement: the device coducts the measurement only when it is on the specifed channel within the hopping sequence. The device puts the measured data together and calculates the performance metrics. The obtained result is the characteristics of the specified channel.
Link-specific measurement: the device conducts the measurement only when it is on a specific link, which is represented by inacLinkilandle defined in Table 8-85. The device puts the measure data together and calculates the performance metrics. The obtained result is the characteristics of the specified link.
In this equation, tx fail time [i] is the time period starting at the first bit of the MPDU and stopping at the end of the last retry time out. The value of j is determined by the number of the failed transmissions within the Measurement time as depicted in Figure 6-79, where the first attempt on the left hand side is successful and not counted as tx fail time [i] and the second attempt on the right hand side is unsuccessful so that it is counted as tx fail time [j]. Also, attempted time [i] is the time when the first frame is attempted to be transmitted to the time when either it is successfully transmitted and acknowledged or it is failed to transmit by reaching macMaxFrameRetries times. Measurement time is defined as the duration of the requested measurement specified by the SRM Duration in Figure 7-136. By considering only the attempted time within the measurement time, the time between any two consecutive attempts, which is idle, is excluded. The accuracy for the time used in this equation shall be土100 us.IEEE Std 802.15.4s pdf download.