Wireless Allowing Data and Power Transfer

Abstract

The WADAPT consortium (Wireless Allowing Data and Power Transfer) was created to study wireless (multi-gigabit) data transfer for high-energy physics applications (LoI, CERN-LHCC-2017-002; LHCC-I-028.-2017). Emerging millimetre wave technologies allow fast signal transfer and efficient partitioning of detectors in topological regions of interest. Large bandwidths are available at those frequencies, allowing very high data rates at short range and conveniently substituting a mass of materials (cables and connectors). The Wadapt initiative aims at building proof of concept for use in future HEP experiments. For vertex detectors at HL-LHC, the bandwidth of 60 GHz is adequate and commercial products are already available, providing 6 Gbps data links. Products have been tested for signal confinement, crosstalk, electromagnetic immunity and resistance to radiation. An HEP dedicated 60 GHz Integrated Chip is being built in Heidelberg, using 130 nm SiGe BICMOS technology. It should assess the feasibility and performance of the wireless link and establish solid foundation for designing the final reading system. At longer terms, 140 GHz bands could also be used for higher data rates (> 100 Gbps) for future FCC applications. Wireless reading could widespread to many detectors, with the possibility of adding intelligence on the detector to perform fourdimensional reconstruction of the traces and vertexes online, in order to attach the traces to their vertex with great efficiency even in difficult experimental conditions. The WADAPT project includes also a long-term step aimed at transmitting energy wirelessly. This would create a new paradigm for the transmission of data and power in particle physics detectors.

Multi Gigabit Wireless Data Transfer in Detectors at Future Colliders

“…According to the Shannon-Hartley theorem, the physical data rate at which information can be transmitted over a communication channel is limited by the channel bandwidth and the signal-tonoise ratio 2 . The fast development of the wireless technologies is linked to the improvements made in the electronics, especially the semiconductor devices and the new simulation capacity [9][10][11][12][13][14][15].…”

“…The performance of non-coherent chips described in [2] was measured at 1-5 cm range between transmitter and receiver using low directivity antenna (Figure 13). The transmitter was fed by a SLVS 8b/10b encoded signal from pseudo random binary sequence at 5 Gbps.…”

“…The present document is based on the work of the whole WADAPT consortium 4 , which has been partly presented at the 40th International Conference on High Energy physics-ICHEP2020 [2]. The authors are grateful to their colleagues of the Heidelberg University, Sebastian Dittmeier, André Schöning, Hans Kristian Soltveit, Dirk Wiedner, for giving them the permission to use in extenso large parts of their publication [26] for the sake of the completeness of this review.…”

“…The WADAPT consortium [1] chose to firstly investigate the relevance of wireless techniques for data transfer within vertex detectors, where commercially-available products in the 60 GHz band [2] would be adequate. The present ATLAS [3] and CMS [4] experiments have been designed for nominal operation at luminosity of 2 × 10 34 cm −2 s −1 and 60 interactions per beam crossing.…”

“…The latest description of the pixel detector layout, including the number of staves per barrel and endcap layer, the number of sensors per stave and the estimated data rates per chip can be found in[6] 2. Here the signal to noise ratio is defined as the average received signal over the bandwidth, and the noise is defined as the average noise or interference power over the bandwidth.…”