Coding and filtering for machine-type communication

Patent metadata

Field	Value
Publication number	US-10021548-B2
Application number	US-201415036740-A
Country	US
Kind code	B2
Filing date	Aug 15, 2014
Priority date	Nov 15, 2013
Publication date	Jul 10, 2018
Grant date	Jul 10, 2018

Abstract

Encoding and decoding schemes at an encoding device/transmitter and decoder device/receiver, respectively, for use in communicating the state of a system. In an example method carried out by an encoding device, state information x(k), which represents the current state of a monitored system, is measured. The encoding device calculates a state update parameter, based on: a message power constraint P; the covariance N of measurement noise associated with the channel over which encoded state information is to be transmitted; and the norm of the signal vector [s(k), x(k)], where s(k) is a stored state information parameter. The encoding device then calculates a message signal z(k)=G(k)*(x(k)−s(k)), which may then be transmitted to a remote decoder device, and calculates an updated version of the stored information s(k+1)=A*(s(k)+F(k)*z(k)). The encoding device replaces the stored state information s(k) with s(k+1).

First claim

What is claimed is:

1. A method, in an encoding device, for communicating a sequential plurality of states of a monitored system, the method having a complexity independent of the number of states comprising the plurality, the method comprising:
receiving measured state information x(k) related to the monitored system;
calculating a state update parameter F(k), based on:
the maximum power P available for transmitting a message over a channel;
a covariance N(k) of measurement noise associated with the channel;
a stored current state information parameter s(k); and
the received measured state information x(k);

calculating a gain parameter G(k) as a function of the maximum power P, the current state information s(k), and the measurement information x(k);
calculating an encoded message z(k) based on the gain parameter G(k) and the difference between the measurement information x(k) and the current state information s(k); and
transmitting the encoded message z(k) to the decoder device via the channel; and
upon receiving an acknowledgement message indicating that the encoded message was successfully received:
calculating an updated current state information s(k+1) based on the stored current state information s(k), the encoded message z(k), and the state update parameter F(k); and
storing the updated current state information s(k+1) as the current state information s(k).

2. The method of claim 1 , wherein the state update parameter F(k) is calculated based on the norm of the vector [s(k), x(k)], and the gain parameter is calculated based on the norm of the difference of x(k) and s(k).

3. The method of claim 1 , wherein the message z(k) is calculated according to z(k)=G(k)*(x(k)−s(k)).

4. The method of claim 1 , further comprising subsequently:
receiving second measured state information x(k+1), the second measured state information x(k+1) representing a second state of the monitored system;
calculating a second state update parameter F(k+1), based on:
the maximum power P;
a second covariance N(k+1) of measurement noise associated with the channel;
the stored current state information parameter s(k+1); and
the received second measured state information x(k+1);

calculating a second gain parameter G(k+1) as a function of the maximum power P, the stored current state information s(k+1), and the received second measurement information x(k+1);
calculating a second encoded message z(k+1) based on the gain parameter G(k) and the difference between the measurement information x(k) and the current state information s(k); and
transmitting the second message signal z(k+1) to the decoder device via the channel.

5. The method of claim 4 , wherein the second covariance N(k+1) and the covariance N(k) are the same, the state update parameter F(k+1) is calculated based on the norm of the vector [s(k+1), x(k+1)], and the gain parameter G(k+1) is calculated based on the norm of the difference of x(k+1) and s(k+1).

6. The method of claim 1 , wherein the state update parameter F(k) is calculated according to F(k)=sigma(k)*√P)/(P+N(k)), where V 11 (0)=V 12 (0)=V 22 (0)=0 and where, for k=0 to a time horizon K:

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Assignees

• Ericsson Telefon Ab L M

Inventors

• Gattami Ather

Classifications

• H04W4/70 Primary

  Services for machine-to-machine communication [M2M] or machine type communication [MTC] · CPC title

• H04L25/0242

  using matrix methods · CPC title

• H03H17/0257

  KALMAN filters · CPC title

• H04L25/0258

  Channel estimation using zero-forcing criteria · CPC title

• H04L1/12

  by using return channel · CPC title