Identification Codes for Wake-Up Signals
Alberto Perotti, Fredrik Berggren, Branislav M. Popović · 2024
This paper presents a new high-rate data encoder structure for Wake-Up Signals (WUS) in wireless networks that serve terminals equipped with low-power wake-up receivers. The encoder yields better missed detection performance compared to uncoded transmissions and prior solutions, whereas its contained complexity copes with low-power receivers' typcal limitations in memory size and processing capability. The encoder uses a maximum distance separable (MDS) or almost-MDS code in order to guarantee low false alarm probability. The terminal identity is encoded by a novel low-complexity method based on associated polynomials (AP) over Galois fields. A randomized rate-matching block selects a given number of consecutive symbols at a random position from the MDS codeword and encodes them by an error correction code. The obtained codeword is modulated and transmitted. Randomized rate-matching provides common randomness be-tween transmitter and receivers, which is needed in order to obtain vanishing false alarm probability according to the Identification via Channels framework [1]. The random number generators (RNG) within rate matching are initialized with a same seed at the transmitter and receivers. Thus, unlike prior solutions, sending transmitter-generated random indices within the WUS is no longer required. This allows usage of stronger error correction codes compared to prior solutions, thereby producing SNR gains larger than 4 dB in terms of missed detection compared to uncoded transmissions, and orders of magnitude false-alarm probability gains. Moreover, the RNG seed is kept confidential among network nodes, thereby preventing generation of counterfeit WUSs by potential attackers.