US 7,613,235 B2
Hitless modem pool expansion at steady state
Maya Bar-El, Hod-Hasharon (Israel); and Zeev Litichever, Rehovot (Israel)
Assigned to Actelis Networks Israel Ltd., Petach Tikvah (Israel)
Appl. No. 10/582,091
PCT Filed Dec. 11, 2003, PCT No. PCT/IL03/01064
§ 371(c)(1), (2), (4) Date Mar. 01, 2007,
PCT Pub. No. WO2005/057806, PCT Pub. Date Jun. 23, 2005.
Prior Publication US 2007/0217489 A1, Sep. 20, 2007
Int. Cl. H04B 1/38 (2006.01)
U.S. Cl. 375—222 24 Claims
OG exemplary drawing
 
1. In a communications system having a first modem transmitting via a communications channel, a method for adding a second modem for communication via said communications channel, the method comprising:
configuring said second modem for receiving communications via said communications channel;
learning crosstalk caused by transmissions from said first modem via said communications channel to said second modem while said second modem is in a transmitting state insufficient to cause crosstalk interference to said first modem in accordance with a predefined measure;
deriving from said learned crosstalk an estimation of crosstalk that would be caused by said second modem to said first modem when said second modem is in a transmitting state;
configuring said first modem to cancel crosstalk according to said crosstalk estimation;
causing said second modem to enter a transmitting state sufficient to cause crosstalk interference to said first modem in accordance with a predefined measure; and
causing said first modem to at least partially cancel crosstalk caused by said second modem in accordance with said crosstalk estimation.