Adaptive Data Decoding

• US 20140270020A1
• Filed: 12/06/2013
• Published: 09/18/2014
• Est. Priority Date: 12/12/2011
• Status: Active Grant

• Current Assignee: John W. Bogdan
• Original Assignee: John W. Bogdan
• Inventors: Bogdan, John W.
• Granted Patent: US 9,136,891 B2
• Time in Patent Office: Days
• US Class Current: 375/346
• CPC Class Codes: H03H 17/0251 Comb filters
• CPC Class Codes: H03H 17/04 Recursive filters
• CPC Class Codes: H04B 1/1027 assessing signal quality or detecting noise/interference for the received signal
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 1/0091 arrangements specific to receivers, e.g. format detection detection of data rate H04L25/0262; detection of coding rate H04L1/0046
• CPC Class Codes: H04L 25/023 with extension to other symbols
• CPC Class Codes: H04L 25/03012 operating in the time domain H04L25/03165, H04L25/03178 take precedence
• CPC Class Codes: H04L 25/0398 Restoration of channel reciprocity
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 27/2657 Carrier synchronisation
• CPC Class Codes: H04L 27/2695 with channel estimation, e.g. determination of delay spread, derivative or peak tracking channel estimation H04L25/0202
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 7/0079 Receiver details

Abstract

This application presents a direct data recovery from subspaces or parameters subranges of a received OFDM signal preidentified as corresponding to specific data symbols, by applying adaptive data decoding (ADD) method for reversing both original data coding and deterministic and random distortions introduced by a transmission channel, wherein both reversals are achieved by the same conversion of the subspaces or parameter subranges into data transmitted originally in order to eliminate an intermediate recovery of signals or parameters transmitted originally within the received OFDM signal. The ADD includes using both amplitudes and gradients of amplitudes of OFDM tone signals.

Claims

1. A method for adaptive data decoding (ADD) from a received OFDM signal combining a reversal of an original data coding made on a transmit side with a reversal of a transformation or distortion introduced by a transmission system, by a direct conversion of parameters of tone signals derived from said received OFDM signal into original data symbols while said received OFDM signal and said tone signals and said parameters remain transformed or distorted by said transmission system;

wherein the ADD method comprises the steps of;

defining sub-ranges of the parameters corresponding to the original data symbols;

defining an assignment of the original data symbols to the defined subranges;

processing the received OFDM signal in order to derive the tone signals and the parameters,

wherein the parameters are derived by using gradients of amplitudes of the tone signals;

recovering the original data symbols corresponding to the received OFDM signal based on the defined assignment of the original data symbols to the defined sub-ranges which the derived parameters belong to.

4. An ADD method as claimed in claim 1, wherein:

the parameters are derived by using the amplitudes of the tone signals instead of using the gradients of the amplitudes of the tone signals.

5. An ADD method as claimed in claim 1, wherein:

the using the gradients of the amplitudes for the deriving the parameters includes calculating integrals of the gradients of the amplitudes over half-cycles of the tone signals.

6. An ADD method as claimed in claim 1, wherein the ADD method comprises using a synchronous circular processor (SCP) for a real time processing of said received OFDM signal;

wherein the SCP comprises;

processing stages which are sequentially connected and fed with samples derived from the received OFDM signal;

wherein the processing stages comprise circular segments designated for storing or processing of consecutive said samples derived from the received OFDM signal;

wherein the storing or processing of the consecutive samples within a particular one of said processing stages is driven by circular clocks applied periodically to consecutive said circular segments contained in the particular one processing stage,

in accordance to an index circulating within a number of the consecutive circular segments contained in the particular one processing stage;

wherein outputs of some of the consecutive circular segments contained in the particular one processing stage can be used in consecutive circular segments contained in a next one of said processing stages,

while other of the consecutive circular segments contained in the particular one processing stage are accepting next said samples.

7. An ADD method as claimed in claim 1, wherein the ADD method comprises using a synchronous sequential processor (SSP) for a real time processing of said received OFDM signal and a programmable control unit (PCU) for a background processing;

wherein;

the PCU is used for the defining the subranges and the defining the assignment based on theoretical models of the transmission channel or a training session or an adaptive analysis of the received OFDM signal;

the PCU is used for controlling operations of the SSP wherein the SSP comprises sequentially connected processing stages driven with clocks synchronous to the OFDM frames and fed with the samples derived from the received OFDM signal.

12. An ADD method as claimed in claim 4, wherein:

the use of the amplitudes for the deriving the parameters includes calculating integrals of the amplitudes over half-cycles or cycles of the tone signals.

13. An ADD method as claimed in claim 4, wherein the ADD method comprises using a synchronous circular processor (SCP) for a real time processing of said received OFDM signal;

wherein the SCP comprises;

processing stages which are sequentially connected and fed with samples derived from the received OFDM signal;

wherein the processing stages comprise circular segments designated for storing or processing of consecutive said samples derived from the received OFDM signal;

wherein the storing or processing of the consecutive samples within a particular one of said processing stages is driven by circular clocks applied periodically to consecutive said circular segments contained in the particular one processing stage,

in accordance to an index circulating within a number of the consecutive circular segments contained in the particular one processing stage;

wherein outputs of some of the consecutive circular segments contained in the particular one processing stage can be used in consecutive circular segments contained in a next one of said processing stages,

while other of the consecutive circular segments contained in the particular one processing stage are accepting next said samples.

14. An ADD method as claimed in claim 4, wherein the ADD method comprises using a synchronous sequential processor (SSP) for a real time processing of said received OFDM signal and a programmable control unit (PCU) for a background processing;

wherein;

the PCU is used for the defining the subranges and the defining the assignment based on theoretical models of the transmission channel or a training session or an adaptive analysis of the received OFDM signal;

the PCU is used for controlling operations of the SSP wherein the SSP comprises sequentially connected processing stages driven with clocks synchronous to the OFDM frames and fed with the samples derived from the received OFDM signal.

2. A method for adaptive data decoding (ADD) from a received OFDM signal combining a reversal of an original data coding made on a transmit side with a reversal of a transformation or distortion introduced by a transmission system, by a direct conversion of subspaces of tone signals derived from said received OFDM signal into original data symbols while said received OFDM signal and said tone signals and said subspaces remain transformed or distorted by said transmission system;

wherein the ADD method comprises the steps of;

deriving reference frames defining the subspaces of the tone signals corresponding to the original data symbols;

defining an assignment of the original data symbols to the defined subspaces;

deriving the tone signals by processing a the received OFDM signal;

deriving parameters of the derived tone signals enabling selection of a particular one of said reference frames or multiple said reference frames which is or are close to the derived tone signals,

wherein the parameters are derived by using amplitudes or gradients of amplitudes of the tone signals;

using the derived parameters for the selection of the particular one reference frame or multiple reference frames;

comparing elements of the tone signals with elements of the selected particular one reference frame or multiple reference frames,

using results of the comparison for identifying the defined subspaces which the derived tone signals belong to;

recovering the original data symbols corresponding to the received OFDM signal based on the defined assignment of the original data symbols to the identified defined subspaces.

8. An ADD method as claimed in claim 2, wherein the ADD method comprises using a synchronous circular processor (SCP) for a real time processing of said received OFDM signal;

wherein the SCP comprises;

processing stages which are sequentially connected and fed with samples derived from the received OFDM signal;

wherein the processing stages comprise circular segments designated for storing or processing of consecutive said samples derived from the received OFDM signal;

wherein the storing or processing of the consecutive samples within a particular one of said processing stages is driven by circular clocks applied periodically to consecutive said circular segments contained in the particular one processing stage,

in accordance to an index circulating within a number of the consecutive circular segments contained in the particular one processing stage;

wherein outputs of some of the consecutive circular segments contained in the particular one processing stage can be used in consecutive circular segments contained in a next one of said processing stages,

while other of the consecutive circular segments contained in the particular one processing stage are accepting next said samples.

9. An ADD method as claimed in claim 2, wherein the ADD method comprises using a synchronous sequential processor (SSP) for a real time processing of said received OFDM signal and a programmable control unit (PCU) for a background processing;

wherein;

the PCU is used for the defining the subspaces and the defining the assignment based on theoretical models of the transmission channel or a training session or an adaptive analysis of the received OFDM signal;

the PCU is used for controlling operations of the SSP wherein the SSP comprises sequentially connected processing stages driven with clocks synchronous to the OFDM frames and fed with the samples derived from the received OFDM signal.

3. A method for adaptive data decoding (ADD) from a received OFDM signal combining a reversal of an original data coding made on a transmit side with a reversal of a transformation or distortion introduced by a transmission system, by a direct conversion of subspaces of tone signals derived from said received OFDM signal into original data symbols while said received OFDM signal and said tone signals and said subspaces remain transformed or distorted by said transmission system;

wherein the ADD method comprises the steps of;

deriving reference frames defining the subspaces of the tone signals corresponding to the original data symbols;

defining an assignment of the original data symbols to the defined subspaces;

deriving the tone signals by processing the received OFDM signal;

identifying the defined subspaces which the derived tone signals belong to, by comparing elements of the derived tone signals with corresponding elements of the derived reference frames;

recovering the original data symbols corresponding to the received OFDM signal based on the defined assignment of the original data symbols to the identified defined subspaces.

10. An ADD method as claimed in claim 3, wherein the ADD method comprises using a synchronous circular processor (SCP) for a real time processing of said received OFDM signal;

wherein the SCP comprises;

processing stages which are sequentially connected and fed with samples derived from the received OFDM signal;

wherein the processing stages comprise circular segments designated for storing or processing of consecutive said samples derived from the received OFDM signal;

wherein the storing or processing of the consecutive samples within a particular one of said processing stages is driven by circular clocks applied periodically to consecutive said circular segments contained in the particular one processing stage,

in accordance to an index circulating within a number of the consecutive circular segments contained in the particular one processing stage;

wherein outputs of some of the consecutive circular segments contained in the particular one processing stage can be used in consecutive circular segments contained in a next one of said processing stages,

while other of the consecutive circular segments contained in the particular one processing stage are accepting next said samples.

11. An ADD method as claimed in claim 3, wherein the ADD method comprises using a synchronous sequential processor (SSP) for a real time processing of said received OFDM signal and a programmable control unit (PCU) for a background processing;

wherein;

the PCU is used for the defining the subspaces and the defining the assignment based on theoretical models of the transmission channel or a training session or an adaptive analysis of the received OFDM signal;

the PCU is used for controlling operations of the SSP wherein the SSP comprises sequentially connected processing stages driven with clocks synchronous to the OFDM frames and fed with the samples derived from the received OFDM signal.