The invention discloses a method for establishing an unconditionally
secure communication model based on combination of beam forming and security coding. The method comprises the steps that a legal sending user sends pre-coded and modulated signals, and an
eavesdropping user receives the signals and calculates an
eavesdropping bit error rate; security coding parameters are calculated, a legal receiving user sends a
pilot frequency sequence, the legal sending user estimates a legal channel, information of the legal channel is extracted, SVD pre-coding is carried out on the signals subjected to security coding and modulation, and the signals are sent; the legal receiving user or the
eavesdropping user receives the signals and carries out decoding
processing and carries out judgment and
demodulation on the decoded signals, security decoding is carried out on a demodulated binary bit
stream, and transmitted signals or eavesdropped signals are acquired. The eavesdropping user lacks information of the legal channel, so that pre-coding
processing of the received signals cannot be relieved, and the
bit error rate is high. The method disclosed by the invention can well achieve establishment of an advantageous channel in an eavesdropping
signal model, and ensure the legal user to receive signals under a low
bit error rate.