In
telecommunications, dirty paper coding (DPC) or Costa precoding is a technique for efficient transmission of
digital
Digital usually refers to something using discrete digits, often binary digits.
Technology and computing Hardware
*Digital electronics, electronic circuits which operate using digital signals
**Digital camera, which captures and stores digital i ...
data through a
channel
Channel, channels, channeling, etc., may refer to:
Geography
* Channel (geography), in physical geography, a landform consisting of the outline (banks) of the path of a narrow body of water.
Australia
* Channel Country, region of outback Austral ...
subjected to some
interference known to the transmitter. The technique consists of
precoding the data in order to cancel the interference. Dirty-paper coding achieves the
channel capacity, without a power penalty and without requiring the receiver to know the interfering signal.
The term ''dirty paper coding'' was coined by Max Costa
[
] who compared the technique to writing a message on a piece of paper which is partially soiled with random ink strokes or spots. By erasing and adding ink in the proper places, the writer can convey just as much information as if the paper were clean, even though the reader does not know where the dirt was. In this analogy, the paper is the channel, the dirt is interference, the writer is the transmitter, and the reader is the receiver.
Note that DPC at the encoder is an
information-theoretic dual
Dual or Duals may refer to:
Paired/two things
* Dual (mathematics), a notion of paired concepts that mirror one another
** Dual (category theory), a formalization of mathematical duality
*** see more cases in :Duality theories
* Dual (grammatical ...
of
Wyner-Ziv coding at the decoder.
Variants
Instances of dirty paper coding include Costa precoding (1983).
Suboptimal approximations of dirty paper coding include Tomlinson-Harashima precoding (THP) published in 1971 and the vector perturbation technique of Hochwald et al. (2005).
Design considerations
DPC and DPC-like techniques require knowledge of the interference state in a non causal manner, such as
channel state information In wireless communications, channel state information (CSI) is the known channel properties of a communication link. This information describes how a signal propagates from the transmitter to the receiver and represents the combined effect of, for ...
of all users and other user data. Hence, the design of a DPC-based system should include a procedure to feed side information to the transmitters.
Applications
In 2003, Caire and Shamai applied DPC to the multi-antenna multi-user downlink, which is referred to as the 'broadcast channel' by information theorists. Since then, there has been widespread use of DPC in
wireless networks and into an interference aware coding technique for dynamic wireless networks.
[
]
Recently, DPC has also been used for "informed
digital watermarking" and is the modulation mechanism used by
10GBASE-T
10 Gigabit Ethernet (10GE, 10GbE, or 10 GigE) is a group of computer networking technologies for transmitting Ethernet frames at a rate of 10 gigabits per second. It was first defined by the IEEE 802.3ae-2002 standard. Unlike previous Eth ...
.
See also
*
Cognitive radio
*
Multiple-input multiple-output communications
In radio, multiple-input and multiple-output, or MIMO (), is a method for multiplying the capacity of a radio link using multiple transmission and receiving antennas to exploit multipath propagation. MIMO has become an essential element of wi ...
*
Multi-user MIMO
Multi-user MIMO (MU-MIMO) is a set of multiple-input and multiple-output (MIMO) technologies for multipath wireless communication, in which multiple users or terminals, each radioing over one or more antennas, communicate with one another. In cont ...
*
Palimpsest
References
{{Reflist
External links
"Writing on Dirty Paper" the original publication by Max Costa
Encodings