A biological status evaluation apparatus comprising: a signal generator configured to generate an electromagnetic signal at one or more frequencies; a transmitting antenna electrically coupled to the signal generator, wherein the transmitting antenna is configured to transmit the electromagnetic signal; a receiving antenna positioned proximate to the transmitting antenna such that an evaluation space is defined between the transmitting antenna and the receiving antenna, wherein: the receiving antenna receives a modulated electromagnetic signal comprising the electromagnetic signal after propagation through the biological tissue under evaluation; a spectrum analyzer coupled to the receiving antenna, wherein the spectrum analyzer receives the modulated electromagnetic signal and samples spectrum data of the modulated electromagnetic signal; and a computing device coupled to the spectrum analyzer, characterized in that: the evaluation space is configured to receive a biological tissue under evaluation such that the biological tissue under evaluation does not contact the transmitting antenna or the receiving antenna; and the computing device calculates an evaluation parameter (Δ) based at least in part on the sampled spectrum data of the modulated electromagnetic signal, wherein said evaluation parameter is calculated by: Δ ≡ ∫ f 0 f 1 df | E T f | 2 − | E R f | 2, where: Δ is the evaluation parameter, E T (f) is the electromagnetic signal as a function of the frequency f, E R (f) is the modulated electromagnetic signal received by the receiving antenna as a function of the frequency f, f 0 is a lower bound of a sampled frequency spectrum, and f 1 is an upper bound of a sampled frequency spectrum; and provides a neurological status indicator of the biological tissue under evaluation based at least in part on the evaluation parameter. a signal generator configured to generate an electromagnetic signal at one or more frequencies; a transmitting antenna electrically coupled to the signal generator, wherein the transmitting antenna is configured to transmit the electromagnetic signal; a receiving antenna positioned proximate to the transmitting antenna such that an evaluation space is defined between the transmitting antenna and the receiving antenna, wherein: the receiving antenna receives a modulated electromagnetic signal comprising the electromagnetic signal after propagation through the biological tissue under evaluation; the receiving antenna receives a modulated electromagnetic signal comprising the electromagnetic signal after propagation through the biological tissue under evaluation; a spectrum analyzer coupled to the receiving antenna, wherein the spectrum analyzer receives the modulated electromagnetic signal and samples spectrum data of the modulated electromagnetic signal; and a computing device coupled to the spectrum analyzer, characterized in that: the evaluation space is configured to receive a biological tissue under evaluation such that the biological tissue under evaluation does not contact the transmitting antenna or the receiving antenna; and the computing device calculates an evaluation parameter (Δ) based at least in part on the sampled spectrum data of the modulated electromagnetic signal, wherein said evaluation parameter is calculated by: Δ ≡ ∫ f 0 f 1 df | E T f | 2 − | E R f | 2, where: Δ is the evaluation parameter, E T (f) is the electromagnetic signal as a function of the frequency f, E R (f) is the modulated electromagnetic signal received by the receiving antenna as a function of the frequency f, f 0 is a lower bound of a sampled frequency spectrum, and f 1 is an upper bound of a sampled frequency spectrum; and provides a neurological status indicator of the biological tissue under evaluation based at least in part on the evaluation parameter. the evaluation space is configured to receive a biological tissue under evaluation such that the biological tissue under evaluation does not contact the transmitting antenna or the receiving antenna; and the computing device calculates an evaluation parameter (Δ) based at least in part on the sampled spectrum data of the modulated electromagnetic signal, wherein said evaluation parameter is calculated by: Δ ≡ ∫ f 0 f 1 df | E T f | 2 − | E R f | 2, where: Δ is the evaluation parameter, E T (f) is the electromagnetic signal as a function of the frequency f, E R (f) is the modulated electromagnetic signal received by the receiving antenna as a function of the frequency f, f 0 is a lower bound of a sampled frequency spectrum, and f 1 is an upper bound of a sampled frequency spectrum; and provides a neurological status indicator of the biological tissue under evaluation based at least in part on the evaluation parameter. Δ is the evaluation parameter, E T (f) is the electromagnetic signal as a function of the frequency f, E R (f) is the modulated electromagnetic signal received by the receiving antenna as a function of the frequency f, f 0 is a lower bound of a sampled frequency spectrum, and f 1 is an upper bound of a sampled frequency spectrum; and provides a neurological status indicator of the biological tissue under evaluation based at least in part on the evaluation parameter.