Distributed Hypothesis Testing with Privacy Constraints

We revisit the distributed hypothesis testing (or hypothesis testing with communication constraints) problem from the viewpoint of privacy. Instead of observing the raw data directly, the transmitter observes a sanitized or randomized version of it. We impose an upper bound on the mutual information between the raw and randomized data. Under this scenario, the receiver, which is also provided with side information, is required to make a decision on whether the null or alternative hypothesis is in effect. We first provide a general lower bound on the type-II exponent for an arbitrary pair of hypotheses. Next, we show that if the distribution under the alternative hypothesis is the product of the marginals of the distribution under the null (i.e., testing against independence), then the exponent is known exactly. Moreover, we show that the strong converse property holds. Using ideas from Euclidean information theory, we also provide an approximate expression for the exponent when the communication rate is low and the privacy level is high. Finally, we illustrate our results with a binary and a Gaussian example

Feedback Enhances Simultaneous Wireless Information and Energy Transmission in Multiple Access Channels

In this report, the fundamental limits of simultaneous information and energy transmission in the two-user Gaussian multiple access channel (G-MAC) with and without feedback are fully characterized. More specifically, all the achievable information and energy transmission rates (in bits per channel use and energy-units per channel use, respectively) are identified. Furthermore, the fundamental limits on the individual and sum- rates given a minimum energy rate ensured at an energy harvester are also characterized. In the case without feedback, an achievability scheme based on power-splitting and successive interference cancellation is shown to be optimal. Alternatively, in the case with feedback (G-MAC-F), a simple yet optimal achievability scheme based on power-splitting and Ozarow's capacity achieving scheme is presented. Finally, the energy transmission enhancement induced by the use of feedback is quantified. Feedback can at most double the energy transmission rate at high SNRs when the information transmission sum-rate is kept fixed at the sum-capacity of the G-MAC, but it has no effect at very low SNRs.Comment: INRIA REPORT N{\deg}8804, accepted for publication in IEEE transactions on Information Theory, March, 201

Linear-Feedback MAC-BC Duality for Correlated BC-Noises, and Iterative Coding

International audienceIn this paper, we show that for the two-user Gaussian broadcast channel with correlated noises and perfect feedback the largest region that can be achieved by linear-feedback schemes equals the largest region that can be achieved over a dual multi-access channel when in this latter the channel inputs are subject to a " non-standard " sum-power constraint that depends on the BC-noise correlation. Combining this new duality result with Ozarow's MAC-scheme gives us an elegant achievable region for the Gaussian BC with correlated noises. We then present a constructive iterative coding scheme for the non-symmetric Gaussian BC with uncorrelated noises that is sum-rate optimal among all linear-feedback schemes. This coding scheme shows that the connection between the MAC and the BC optimal schemes is tighter than what is suggested by our duality result on achievable rates. In fact, it is linear-feedback sum-rate optimal to use Ozarow MAC-encoders and MAC-decoders— rearranged—to code over the BC

Decentralized Simultaneous Energy and Information Transmission in Multiple Access Channels

International audienceIn this paper, the fundamental limits of decentralized simultaneous information and energy transmission in the two-user Gaussian multiple access channel (G-MAC) are fully characterized for the case in which a minimum energy transmission rate b is required for successful decoding. All the achievable and stable information-energy transmission rate tuples (R1, R2, B) are identified. R1 and R2 are in bits per channel use measured at the receiver and B is in energy units per channel use measured at an energy-harvester (EH). Stability is considered in the sense of an η-Nash equilibrium (NE), with η>=0 arbitrarily small. The main result consists of the full characterization of the η-NE information-energy region, i.e., the set of information-energy rate triplets (R1, R2, B) that are achievable and stable in the G-MAC when: (a) both transmitters autonomously and independently tune their own transmit configurations seeking to maximize their own information transmission rates, R1 and R2 respectively; (b) both transmitters jointly guarantee an energy transmission rate B at the EH, such that B>=b. Therefore, any rate triplet outside the η-NE region is not stable as there always exists one transmitter able to increase by at least η bits per channel use its own information transmission rate by updating its own transmit configuration

Simultaneous Energy and Information Transmission in Gaussian Multiple Access Channels

International audienceIn this paper, simultaneous wireless information and energy transmission is studied from an information theoretic standpoint. The main contribution is twofold: (i) the capacity-energy region of the memoryless Gaussian multiple access channel is fully characterized; and (ii) the maximum sum-rate that can be achieved when a minimum energy level is required at the input of the receiver is determined. In particular, it is shown that the sum-capacity for a given energy threshold can be achieved by a simple power-splitting scheme

Decentralized Simultaneous Energy and Information Transmission in Multiple Access Channels

In this report, the fundamental limits of decentralized simultaneous information and energy transmission in the two-user Gaussian multiple access channel (G-MAC) are fully characterized for the case in which a minimum energy transmission rate b is required for successful decoding. All the achievable and stable information-energy transmission rate tuples (R_1, R_2, B) are identified. R_1 and R_2 are in bits per channel use measured at the receiver and B is in energy units per channel use measured at an energy-harvester (EH). Stability is considered in the sense of an η-Nash equilibrium (NE), with η >= 0 arbitrarily small. The main result consists of the full characterization of the η-NE information-energy region, i.e., the set of information-energy rate triplets (R_1,R_2,B) that are achievable and stable in the G-MAC when: (a) both transmitters autonomously and independently tune their own transmit configurations seeking to maximize their own information transmission rates, R_1 and R_2 respectively; (b) both transmitters jointly guarantee an energy transmission rate B at the EH, such that B >= b.Therefore, any rate triplet outside the η-NE region is not stable as there always exists one transmitter able to increase by at least η bits per channel use its own information transmission rate by updating its own transmit configuration.Dans le présent-rapport, les limites fondamentales de la transmission décentralisée et simultanée de l'information et de l'énergie dans les canaux Gaussiens à accès multiple à deux utilisateurs (G-MAC) sont déterminées dans le cas où un débit minimal b de transmission d'énergie est requis pour un décodage réussi. Tous les triplets de débits atteignables et stables de transmission d'énergie et d'information (R_1,R_2,B) sont identifiés. Les débits d'information R_1 et R_2 en bits par utilisation canal sont mesurés au niveau du récepteur et le débit d'énergie B en unités d'énergie par utilisation canal est mesuré au niveau d'un collecteur d'énergie.La stabilité est considérée au sens d'un η-équilibre de Nash ( η-NE), avec η >= 0 arbitrairement petit. Le résultat principal est la caractérisation complète de la région η-NE d'information-énergie, i.e., l'ensemble des triplets d'information-énergie (R_1,R_2,B) qui sont atteignables et stable dans le G-MAC quand: (a) les deux transmetteurs règlent leurs configurations d'émission d'une manière autonome et indépendante dans le but de maximiser leurs débits individuels de transmission d'information R_1 et R_2, respectivement; (b) les deux transmetteurs garantissent conjointement un débit de transmission d'énergie B au niveau du collecteur d'énergie tel que B >= b. Par conséquent, tout triplet en dehors de la région η-NE n'est pas stable car il doit toujours y avoir un transmetteur qui soit capable d'augmenter son débit d'information par au moins η bits par utilisation canal en ajustant sa propre configuration d'émission

Feedback Enhances Simultaneous Wireless Information and Energy Transmission in Multiple Access Channels

International audienceIn this paper, the fundamental limits of simultaneous information and energy transmission in the two-user Gaussian multiple access channel (G-MAC) with and without feedback are fully characterized. More specifically, all the achievable information and energy transmission rates (in bits per channel use and energy-units per channel use, respectively) are identified. Furthermore, the fundamental limits on the individual and sum-rates given a minimum energy rate ensured at an energy harvester are also characterized. In the case without feedback, an achievability scheme based on power-splitting and successive interference cancellation is shown to be optimal. Alternatively, in the case with feedback (G-MAC-F), a simple yet optimal achievability scheme based on power-splitting and Ozarow's capacity achieving scheme is presented. Finally, the energy transmission enhancement induced by the use of feedback is quantified. Feedback can at most double the energy transmission rate at high SNRs when the information transmission sum-rate is kept fixed at the sum-capacity of the G-MAC, but it has no effect at very low SNRs. Index Terms—Feedback, Gaussian multiple access channel, simultaneous information and energy transmission, RF harvesting, information-energy capacity region

Feedback Enhances Simultaneous Wireless Information and Energy Transmission in Multiple Access Channels

accepted for publication in IEEE Transactions on Information Theory, March 2017.In this report, the fundamental limits of simultaneous information and energy transmission in the two-user Gaussian multiple access channel (G-MAC) with and without feedback are fully characterized. More specifically, all the achievable information and energy transmission rates (in bits per channel use and energy-units per channel use, respectively) are identified. Furthermore, the fundamental limits on the individual and sum- rates given a minimum energy rate ensured at an energy harvester are also characterized. In the case without feedback, an achievability scheme based on power-splitting and successive interference cancellation is shown to be optimal. Alternatively, in the case with feedback (G-MAC-F), a simple yet optimal achievability scheme based on power-splitting and Ozarow's capacity achieving scheme is presented. Finally, the energy transmission enhancement induced by the use of feedback is quantified. Feedback can at most double the energy transmission rate at high SNRs when the information transmission sum-rate is kept fixed at the sum-capacity of the G-MAC, but it has no effect at very low SNRs.Dans le présent-rapport, les limites fondamentales de la transmission simultanée d'information et d'énergie dans le canal Gaussien à accès multiple (G-MAC) avec et sans voie de retour sont déterminées.L'ensemble des débits atteignables de transmission d'information et d'énergie (en bits par utilisation canal et en unités d'énergie par utilisation canal respectivement) est identifié.En outre, on caractérise les limites fondamentales sur les débits individuels et le débit-somme de transmission de l'information pour un débit d'énergie donné à l'entrée d'un collecteur d'énergieDans le cas sans voie de retour, on démontre qu'un schéma d'atteignabilité, basé sur la division de puissance et sur l'annulation successive de l'interférence, est optimal.En contrepartie, dans le cas avec voie de retour (G-MAC-F), un schéma d'atteignabilité, simple mais optimal, basé sur la division de puissance et sur le schéma d'Ozarow qui atteint la capacité, est présenté. Finalement, le gain en énergie induit par l'exploitation de la voie de retour est quantifié. La voie de retour peut au mieux dédoubler le débit d'énergie à fort rapport signal sur bruit (RSB) pour un débit-somme d'information égal à la capacité-somme. En revanche, l'utilisation de la voie de retour n'a aucun effect à très faibles RSBs