Using deterministic decisions for low-entropy bits in the encoding and decoding of polar codes

When blended together, homopolymers A and B will normally macrophase-separate into relatively large (≫1 μm) A-rich and B-rich phases, between which exists poor interfacial adhesion, due to a low entropy of mixing. The size scale of phase separation in such a blend can be reduced, and the extent of interfacial A-B contact and entanglement enhanced, via addition of an emulsifying agent such as an AB diblock copolymer. Diblock copolymers consist of a long sequence of A monomers covalently bonded to a long sequence of B monomers. These materials are surface-active and decrease interfacial tension between immiscible phases much in the same way as do small-molecule surfactants. Previous studies have clearly demonstrated the utility of block copolymers in compatibilizing homopolymer blends and enhancing blend properties such as fracture toughness. It is now recognized that optimization of emulsified ternary blends relies upon design considerations such as sufficient block penetration into a macrophase (to avoid block slip) and prevention of a copolymer multilayer at the A-B interface (to avoid intralayer failure).

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An Adaptive Fusion Successive Cancellation List Decoder for Polar Codes with Cyclic Redundancy Check

IEICE Transactions on Communications ◽

10.1587/transcom.2019ebp3031 ◽

2020 ◽

Vol E103.B (1) ◽

pp. 43-51 ◽

Cited By ~ 1

Author(s):

Yuhuan WANG ◽

Hang YIN ◽

Zhanxin YANG ◽

Yansong LV ◽

Lu SI ◽

...

Keyword(s):

Polar Codes ◽

Cyclic Redundancy Check ◽

Successive Cancellation ◽

Adaptive Fusion ◽

List Decoder

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Compact specification of polar codes

Information and Control Systems ◽

10.31799/1684-8853-2019-1-40-47 ◽

2019 ◽

pp. 40-47

Author(s):

R. A. Morozov ◽

P. V. Trifonov

Keyword(s):

Storage Capacity ◽

Low Complexity ◽

Practical Implementation ◽

Polar Codes ◽

Practical Relevance ◽

Memory Consumption ◽

Full Size ◽

The Family ◽

Erasure Probability ◽

Binary Erasure Channel

Introduction:Practical implementation of a communication system which employs a family of polar codes requires either to store a number of large specifications or to construct the codes by request. The first approach assumes extensive memory consumption, which is inappropriate for many applications, such as those for mobile devices. The second approach can be numerically unstable and hard to implement in low-end hardware. One of the solutions is specifying a family of codes by a sequence of subchannels sorted by reliability. However, this solution makes it impossible to separately optimize each code from the family.Purpose:Developing a method for compact specifications of polar codes and subcodes.Results:A method is proposed for compact specification of polar codes. It can be considered a trade-off between real-time construction and storing full-size specifications in memory. We propose to store compact specifications of polar codes which contain frozen set differences between the original pre-optimized polar codes and the polar codes constructed for a binary erasure channel with some erasure probability. Full-size specification needed for decoding can be restored from a compact one by a low-complexity hardware-friendly procedure. The proposed method can work with either polar codes or polar subcodes, allowing you to reduce the memory consumption by 15–50 times.Practical relevance:The method allows you to use families of individually optimized polar codes in devices with limited storage capacity.

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