SummaryConventional‐generalized spatial modulation (C‐GSM) is an multiple‐input multiple‐output (MIMO) spatial modulation (SM) scheme that transmits the same complex amplitude/phase modulation symbol from multiple active transmit antennas. By using two active transmit antennas during a transmission interval, C‐GSM is capable of achieving high spectral efficiencies. However, as the size of the signal constellation/domain increases, the minimum Euclidean distances (ED) between the symbols decrease. Hence, this leads to a degradation of the average bit error rate (ABER) performance of the scheme. Hence, motivated to improve the error performance of C‐GSM schemes, first, this study proposes a new scheme called Golden codeword‐based generalized spatial modulation (GCW‐GSM), which combines C‐GSM and the Golden code to take advantage of the benefits of both while avoiding their drawbacks. The proposed scheme uses conventional quadrature amplitude modulation (C‐QAM), and it is investigated over Rayleigh frequency‐flat fading channels with additive white Gaussian noise. Second, a closed‐form expression of the theoretical average bit error probability of the proposed GCW‐GSM scheme is formulated. Compared to simulation results, it proves to be increasingly tight at high signal‐to‐noise ratio values. Finally, the proposed scheme performance over the Rayleigh‐frequency‐flat fading channel is compared to that over the Rician channel. An improvement in the error performance of with spectral efficiency of is seen in C‐16QAM GCW‐GSM over C‐256QAM conventional‐spatial modulation and C‐256QAM C‐GSM schemes at a bit error rate (BER) of . The C‐16QAM GCW‐GSM scheme exhibits an improvement in the error performance of with spectral efficiency of over the C‐64QAM conventional quadrature spatial modulation scheme at a BER of . Finally, the 16‐QAM GCW‐GSM under Rayleigh fading has a performance gain of 3 dB over 16‐QAM GCW‐GSM under Rician fading with a Rician K factor of 3.