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The design of complex analog interfaces would largely benefit from model-based development and compositional methods to improve the quality of its final result. However, analog circuit behaviors are so tightly intertwined with their environment that: 1) abstractions needed for model-based design are often not accurate, thus making it difficult to achieve reliable system performance estimations, and 2) generic, designindependent interfaces that are needed to develop compositional techniques are very difficult to define. In this paper, we propose a platform-based design methodology that uses analog contracts to develop reliable abstractions and design-independent interfaces. A contract explicitly handles pairs of properties, representing the assumptions on the environment and the promises of a component under these assumptions. Horizontal contracts encode composition rules that constrain how library elements should be "legally" used. Vertical contracts define under which conditions an aggregation of components satisfies the requirements posed at a higher level of abstraction. If both sets of contracts are satisfied, we can produce implementations by composition and refinement that are correct by construction. We demonstrate the effectiveness of this approach on the design of an ultra-wide band receiver used in an Intelligent Tire system, an on-vehicle wireless sensor network for active safety applications.Index Terms-Analog and mixed-signal design, automotive sensor interfaces, contract-based design, integrated sensor interface modeling, platform-based design, ultrawideband.

diodes, lasers, and solar cell applications due to its excellent optoelectronic properties with a strong tunability by varying composition and crystal structure. [1] However, the top-performing Pb-based perovskite materials suffer from two major drawbacks, namely, the toxicity of heavymetal Pb and its intrinsic instability to the external environments (heating, moisture, light, and air), which seriously restrict their commercialization and industrial production in the future practical applications. [2] To overcome these bottlenecks, metal halide double perovskites with a formula of A 2 B I B III X 6 have been proposed and synthesized as the most promising alternatives due to their a persistent stability and diverse optical properties stemming from the flexible manipulation of component combination. [3] To date, the performance of double perovskites is unsatisfactory and far below expectations. All the systems exhibit an extremely weak photoluminescence (PL), which is mainly attributed to the large, indirect bandgap or the parity-forbidden direct bandgap with a weak oscillator strength, results in the nonradiative recombination of carriers. [4] To enhance emission efficiency of those materials, doping engineering in double perovskites was carried out to tune their intrinsic physical and chemical characteristics with the modified optical properties. [5] Efficient Mn-dopant emission originating from 4 T 1 to 6 A 1 transition was achieved by doping Mn 2+ ions into double perovskite Cs 2 NaBiCl 6 lattice, in which the Mn-dopant randomly occupied the site of Na + or Bi 3+ ions to form [MnCl 6 ] 4− octahedra. [6] However, Mn 2+ incorporation into the Cs 2 NaBiCl 6 lattice is limited with to a doping level of 2-3%, thus restricting the population of Mn 2+ luminescence centers. [6a] The previous investigations demonstrated that the PL intensity of Mn 2+ dopants strongly depends on the doped radial positions inside core/shell nanocrystals and is associated with the modulation of wave functions coupled between the dopant and host, [7] indicating that the emission performance of Mn-doped Cs 2 NaBiCl 6 system can be optimized by tuning the electronic wave function coupling between Bi 3+ and Mn 2+ ions. Pressure is a powerful and clean tool to modify the electronic structure and optical properties of various materials by lattice Pressure engineering can access novel optoelectronic properties and crystal structures in halide perovskite materials with soft lattice. However, such pressure-induced phenomena are commonly realized under large pressure or difficult to retain at atmospheric pressure, thus severely hindering their prospects in practical applications. Herein, the pressure-treated Mn-doped/ undoped Cs 2 NaBiCl 6 exhibits a largely retained bandgap narrowing of 12.2% relative to its initial state via compression-decompression cycles, along with durable stability at ambient conditions. This abnormal behavior is attributed to the disordered arrangement of inorganic [NaCl 6 ] 5− /[BiCl 6 ] 3− octahedra, which occurs i...

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