This introduction is not part of IEEE Std 802.15.4t-2017@ IEEE Standard for Low-Rate Wireless Networks@ Amendment 4: Higher Rate (2 Mb/s) Physical (PHY) Layer This amendment defines an additional data rate for the minimum shift keying (MSK) PHY specified in IEEE Std 802.15.4-2015@ and any MAC modifications needed to support its implementation. The new data rate@ 2000 kbps@ is specified for the 2400-2483.5 MHz band@ and has the same occupied bandwidth as the present 2450 MHz 0-QPSK physical layer. This data rate enables the use of devices with low energy consumption that operate in short@ high-speed bursts@ followed by relatively long sleep periods@ resulting in a low-rate network with improved battery life.