  As a generalization of cyclic codes, quasi-cyclic (QC) codes contain many
good linear codes. But quasi-cyclic codes studied so far are mainly limited to
one generator (1-generator) QC codes. In this correspondence, 2-generator and
3-generator QC codes are studied, and many good, new QC codes are constructed
from simplex codes. Some new binary QC codes or related codes, that improve the
bounds on maximum minimum distance for binary linear codes are constructed.
They are 5-generator QC [93, 17, 34] and [254, 23, 102] codes, and related [96,
17, 36], [256, 23, 104] codes.
