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How do I increase RF and Power Efficiency?


Low Duty Cycle (LDC) and Single Target Inventory with Suppression (S1 Refresh) are exclusive features of all Impinj Speedway readers including the Speedway Revolution reader and Speedway xPortal gateway.

LDC enables the reader to go into a low power and low transmit mode when tags are not visible in the antenna field of view. The reader then “pings” for tags at a set interval dramatically reducing power consumption and unnecessary transmissions. When its “ping” sees a tag in the field, the reader will automatically exit LDC and begin reading tags.

Using S1 Refresh instructs the reader to continually refresh the Impinj Monza chip’s S1 flag preventing the Monza chip from being re-read while illuminated by the antenna. The reader will automatically come out of LDC mode only when new tags are in the field or when Impinj Monza chips are not able to hear the S1 refresh select command from the reader. This feature is only supported when using tags with Impinj Monza chips inside.

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Impinj (NASDAQ: PI) wirelessly connects billions of everyday items such as apparel, medical supplies, and automobile parts to consumer and business applications such as inventory management, patient safety, and asset tracking. The Impinj platform uses RAIN RFID, delivering information about items to the digital world and enabling the Internet of Things.