Patent ID: 7426664

Claim:
A method for testing a bit error ratio BER of a device against a maximal allowable Error Ratio BER limit with an early pass criterion, whereby the early pass criterion is allowed to be wrong only by a small probability D 1 , comprising the following steps measuring ns bits of the output of the device, thereby detecting ne erroneous bits of these ns bits; assuming that the likelihood distribution giving a distribution of the number of erroneous bits ni in a fixed number of samples of bits is PD(NE,ni), wherein NE is an average number of erroneous bits, obtaining PD high from D 1 = ∫ 0 n ⁢ ⁢ e ⁢ PD high ⁡ ( NE high , ni ) ⁢ ⅆ ni wherein PD high is the worst possible likelihood distribution containing the measured ne erroneous bits with the probability D 1 ; obtaining the average number of erroneous bits NE high for the worst possible likelihood distribution PD high ; comparing NE high with NE limit =BER limit ns; if NE limit is higher than NE high stopping the test and deciding that the device has early passed the test; and if NE limit is smaller than NE high continuing the test whereby increasing ns.