Dynamic FD coexistence method for PLC systems

• US 20060073805A1
• Filed: 09/30/2005
• Published: 04/06/2006
• Est. Priority Date: 10/04/2004
• Status: Active Grant

• Current Assignee: Sony Deutschland GmbH (Sony Group Corp.)
• Original Assignee: Sony Deutschland GmbH (Sony Group Corp.)
• Inventors: Tiedemann, Stephen, Gaedeken, Gralf, Zumkeller, Markus, Stadelmeier, Lothar, Schwager, Andreas
• Granted Patent: US 7,702,085 B2
• Time in Patent Office: Days
• US Class Current: 455/402
• CPC Class Codes: H04B 15/005 Reducing noise, e.g. humm, from the supply
• CPC Class Codes: H04B 17/309 Measuring or estimating channel quality parameters
• CPC Class Codes: H04B 2203/5408 using protocols
• CPC Class Codes: H04B 2203/5416 by adding signals to the wave form of the power source
• CPC Class Codes: H04B 2203/5425 improving S/N by matching impedance, noise reduction, gain control
• CPC Class Codes: H04B 2203/5445 Local network
• CPC Class Codes: H04B 2203/5495 having measurements and testing channel
• CPC Class Codes: H04B 3/54 Systems for transmission via power distribution lines
• CPC Class Codes: H04B 3/542 the information being in digital form
• CPC Class Codes: H04L 27/2637 with direct modulation of individual subcarriers
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling

Abstract

A power line communication method is provided for realizing data communication between at least one first or sending power line communication partner device (P1) and at least one second or receiving power line communication partner device (P10). The inventive method comprises a step of checking transmission conditions of a plurality of possible communication channels (Ch1, . . . , Chn). Thereby generating transmission condition data which are descriptive for the communication conditions of the respective possible communication channels (Ch1, . . . , Chn). Additionally, a step of selecting communication conditions of the plurality of possible communication channels (Ch1, . . . , Chn) as actual communication conditions based on said transmission condition data.

Claims

1. Power line communication method for realizing data communication between at least one first or sending power line communication partner device (P1) and at least one second or receiving power line communication partner device (P10) of a power line communication system (P),

comprising:

(a) a step of checking transmission conditions of a plurality of possible communication channels (Ch1, . . . , Chn) between said at least one first or sending power line communication partner device (P1) and said at least one second or receiving power line communication partner device (P10), thereby generating transmission condition data which are descriptive for the transmission conditions of the respective possible communication channels (Ch1, . . . , Chn) and

(b) a step of selecting communication conditions of the plurality of possible communication channels (Ch1, . . . , Chn) as actual communication conditions based on said transmission condition data between said at least one first or sending power line communication partner device (P1) and said at least one second or receiving power line communication partner device (P10).

2. Method according to claim 1,

wherein said transmission condition data are generated in order to describe at least one of the group comprising a signal to noise ratio, time slots, frequency bands, channel capacities, interference signals from power line communication partner devices of said power line communication system (P) or of other systems (P′

) of possible power line communication channels (Ch1, . . . , Chn), ground noise, and interferences from non power line communication devices.

3. Method according to claim 1, wherein said actual communication conditions are chosen in order to effect and select at least one of the group comprising a frequency band, a signal modulation scheme, a time slot and an emission power of a possible or said actual communication channel (Ch1, . . . , Chn) of the plurality of possible communication channels (Ch1, . . . , Chn) between said at least one first or sending power line communication partner device (P1) and said at least one second or receiving power line communication partner device (P10).

4. Method according to claim 1, wherein said step (a) of checking transmission conditions is carried out repeatedly.

5. Method according to claim 1, wherein said step (a) of checking transmission conditions is carried out during a process of data communication in progress between said at least one first or sending power line communication partner device (P1) and said at least one second or receiving power line communication partner device (P10).

6. Method according to claim 1, wherein said step (b) of selecting said communication conditions is carried out repeatedly.

7. Method according to claim 1, wherein said step (b) of selecting said communication conditions is carried out during a process of data communication and progress between said at least one first or sending power line communication partner device (P1) and said at least one second or receiving power line communication partner device (P10), in order to change its communication conditions for maintaining or increasing the actual data communication quality of the data communication between said at least one first or sending power line communication partner device (P1) and said at least one second or receiving power line communication partner device (P10) in progress.

8. Method according to claim 1, wherein said actual communication conditions are chosen according to a given threshold criterion, in particular with respect to at least one of said transmission parameters.

9. Method according to claim 1, wherein said actual communication conditions are chosen in order to realize a best data communication, in particular with respect to a given threshold criterion, in particular with respect to at least one of said transmission parameters.

10. Method according to claim 1, wherein signal emission for data communication between said at least one first or sending power line communication partner device (P1) and said at least one second or receiving power line communication partner device (P10) is reduced or avoided by said at least one first or sending power line communication partner device (P10) for frequency bands in which said at least one second or receiving power lien communication partner device (P10) does not listen and/or in which foreign sending devices or noise are present.

11. Method according to claim 1, wherein signal emission power for data communication between said at least one first or sending power line communication partner device (P1) and said at least one second or receiving power line communication partner device (P10) is set in order to fulfil given emission power limit requirements with respect to chosen emission frequency bands.

12. Method according to claim 1, wherein data communication between said at least one first or sending power line communication partner device (P1) and said at least one second or receiving power line communication partner device (P10) is established according to a media access control or MAC structure.

13. Method according to claim 1, wherein a channel capacity (C) is evaluated according to Shannon'"'"'s law and in particular according to the following formula (1):

$\begin{array}{cc}C={\int <br><br>}_{t_{\mathrm{start}}}^{t_{\mathrm{stop}}}<br><br>{\int <br><br>}_{f_{\mathrm{start}}}^{f_{\mathrm{stop}}}<br><br>l<br><br>\text{\hspace{1em}<br><br>}<br><br>d<br><br>\left(1+\mathrm{SNR}\right)<br><br>d<br><br>f<br><br>d<br><br>t& \left(1\right)\end{array}$

wherein C denotes the channel capacity, t denotes the time variable for data transmission, t_start denotes the starting time, t_stop denotes the stopping time, f denotes the frequency variable, f_start denotes the starting frequency, f_stop denotes the stopping frequency, ld(·

) denotes the dual logarithmic function, and SNR denotes the respective signal-to-noise-ratio.

14. Method according to claim 1, wherein for a plurality of time gaps with respective starting times t_start,l, . . . , t_start,n and stopping times t_stop,l, . . . , t_stop,n fulfilling the conditions t_start,j≦

t_start,j+1, t_stop,j≦

t_stop,j+1, and t_start,j<

t_stop,j for j=1, . . . , n and/or for a plurality of frequency gaps with respective starting frequencies f_start,l, . . . , f_start,m and stopping frequencies f_stop,l, . . . , f_stop,m fulfilling the conditions f_start,k≦

f_start,k+1, f_stop,k≦

f_stop,k+1, and f_start,k<

f_stop,k for k=1, . . . , m a full channel capacity C_full is evaluated according to the following formula (2a);

$\begin{array}{cc}{C}_{\mathrm{full}}=\underset{j=1}{\overset{n}{\sum <br><br>}}<br><br>\text{\hspace{1em}<br><br>}<br><br>\underset{k=1}{\overset{m}{\sum <br><br>}}<br><br>\text{\hspace{1em}<br><br>}<br><br>C_{j,k}& \left(2<br><br>a\right)\end{array}$

wherein C_j,k denotes the partial channel capacity for the j^th time gap and the k_th frequency gap and is determined according to Shannon'"'"'s law and in particular according to the following formula (2b);

$\begin{array}{cc}{C}_{j,k}={\int <br><br>}_{t_{\mathrm{start},j}}^{t_{\mathrm{stop},j}}<br><br>\text{\hspace{1em}<br><br>}<br><br>{\int <br><br>}_{f_{\mathrm{start},k}}^{f_{\mathrm{stop},k}}<br><br>l<br><br>\text{\hspace{1em}<br><br>}<br><br>d<br><br>\left(1+\mathrm{SNR}\right)<br><br>d<br><br>f<br><br>d<br><br>t& \left(2<br><br>b\right)\end{array}$

wherein t denotes the time variable for data transmission, f denotes the frequency variable, ld(·

) denotes the dual logarithmic function, and SNR denotes the respective signal-to-noise-ratio.

15. Method according to claim 1, wherein a signal to noise ratio (SNR) is determined according to the following formula (3):

SNR=PSD_feed−

ATT−

NPSD_receive 

 

(3)

wherein SNR denotes the respective signal to noise ratio, PSD_feed denotes the feeding power spectral density, which is in particular known to all modems, NPSD_receive denotes the noise power spectral density at a receiver, which is in particular measured by the receiving power line communication partner device (P10), and ATT denotes the attenuation of a signal, in particular between said first or sending power line communication partner device (P1) and said second or receiving power line communication partner device (P10).

16. Method according to claim 1, wherein a plurality of power line communication systems (P, P′

) as managed, in particular each having a plurality of power line communication partner devices (P1, P10;

P15, P21) and/or each without inter system communication between each of said systems of said plurality of power line communication systems (P, P′

).

17. System, which is adapted and/or arranged and which has means in order to realize a method for power line communication according to claim 1.

18. Power line communication device which is adapted and/or arranged and which has means in order to realize and/or to participate a/two method for power line communication according to claim 1.

19. Computer program product, comprising computer means which is adapted and/or arranged in order to realize a method for power line communication according to claim 1 and the steps thereof when it is executed on a computer, a digital signal processing means or the like.

20. Computer readable storage medium comprising a computer program product according to claim 19.