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Physical layer attacks allow attackers to manipulate (spoof) ranging and positioning. These attacks had real world impact and allowed car thefts, executions of unauthorised payments and manipulation of navigation. UWB impulse radio (UWB-IR) has emerged as a prominent technique for precise ranging that allows high operating distances despite power constraints by transmitting multi-pulse symbols. Unfortunately, longer symbols make UWB-IR vulnerable to physical layer attacks. Currently, none of the existing systems is precise, performant and secure at the same time. We present UWB with Pulse Reordering (UWB-PR), the first modulation scheme that secures distance measurement between two mutually trusted devices against all physical-layer attacks.

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Ne present the general properties o f jets produced by e+e' annihilation.Their production and fragmentation characteristics have been studied w i t h charged p a r t i c l e s for c.m. energies between 12 and 43 GeV. In this energy range e+e' annihilation into hadrons i s dominated by pair production o f the f i v e quarks u ‚ d , s ‚ c and b . In addition, hard gluon bremsstrahlung effects which are i n v i s i b l e a t low energies become prominent at the high energies.The observed multiplicity distributions deviate from a Poisson distribution. The m u l t i p l i c i t y distributions for the overall event as well as for each event hemisphere s a t i s f y KNO s c a l i n g to w i t h i n "20 %. The distributions o fxp = 2p/W are presented; scale breaking i s observed a t the l e v e l o f 25 %.The quantity xp dcr/dxp i s compared w i t h multigluon emission calculations which predict a Gaussian distribution i n terms o f ß n ( 1 / x ) . The observed energy dependence o f the maximum o f the distributions i s i n qualitative agreement with the calculations. P a r t i c l e production i s analysed w i t h respect to the jet a x i s and longitudinal and transverse momentum spectra are pre-' sented. The angular distribution o f the j e t a x i s strongly supports the idea o f predominant spin 1/2 quark p a i r production. The p a r t i c l e distributions w i t h respect t o the event plane show clearly the growing importance o f planar events with increasing c.m. energies. They a l s o exclude the presence of heavy quark production, e+e_ + 00, for quark masses up to _. 5 < mQ < 20.3 GeV ([eQI = 2/3) and.J < mQ < 19 GeV ( l t = 1/3). The comparison o f 1/otot do/d measured a t 14, 22 and 34 GeV suggests that hard gluon bremsstrahlung contributes mainly to transverse momenta larger than 0 . 5 GeV/c. The rapidity distribution for w 3 22 GeV shows an enhancement away from y = 0 which corresponds to an increase i n y i e l d o f 10 -15 % compared to the centre region ( y = 0 ) . The enhancement probably results from heavy quark production and gluon bremsstrahlung. The p a r t i c l e f l u x around the jet axis shows w i t h increasing c.m. energy a rapidly growing number o f particles collimated around the j e t a x i s , w h i l e a t large angles t o the j e t a x i s almost no W dependence i s _ o b s e r v e d . For f i x e d longitudinal momentum p|| approximate " f a n invariance" i s seen: The shape of the angular distribution around the jet a x i s i s almost independent o f w. The collimation depends strongly on p". For small p"‚ p" < 0 . 2 GeV/c, isotropy i s observed.With increasing p" the particles tend to be emitted closer and c l o s e r t o the jet a x i s .

Future transportation systems highly rely on the integrity of spatial information provided by their means of transportation such as vehicles and planes. In critical applications (e.g. collision avoidance), tampering with this data can result in life-threatening situations. It is therefore essential for the safety of these systems to securely verify this information. While there is a considerable body of work on the secure verification of locations, movement of nodes has only received little attention in the literature. This paper proposes a new method to securely verify spatial movement of a mobile sender in all dimensions, i.e., position, speed, and direction. Our scheme uses Doppler shift measurements from different locations to verify a prover's motion. We provide formal proof for the security of the scheme and demonstrate its applicability to air traffic communications. Our results indicate that it is possible to reliably verify the motion of aircraft in currently operational systems with an equal error rate of zero.

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