One embodiment is directed to a method comprising deciding to multiplex the data of at least two users within a super-constellation; determining the power split ratio among the at least two users; selecting a super-constellation; and based on the determined power split ratio, choosing a subset of the super-constellation points forming the superposition of modulation constellations of the at least two users.

A Radio Network Node (RNN) 110 and a method therein for improving capacity in a wireless communications system 100. The RNN is configured to serve a first wireless device 120 and a second wireless device (WD) 130. The RNN assigns a shared uplink pilot signal to the first and second WDs. Further, the RNN transmits, to the first WD, an indication of how possible second data intended for the second WD will be comprised in a signal to be transmitted to the first WD. Furthermore, the RNN estimates a combined channel based on a received shared uplink pilot signal from the first WD and/or the second WD. Yet further, the RNN determines a beamforming vector for the estimated combined channel; and transmits the signal to the first WD, wherein the signal comprises first data and the possible second data, which first data is decodable only by the first WD.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) generates multiple systematic bits for a message, where the systematic bits are nonuniformly distributed over a time period such that a first bit value has a first probability of occurrence during the time period and a second bit value has a second probability that is greater than the first probability of the occurrence. The UE modulates the systematic bits according to an asymmetric modulation rule such that the first bit value corresponds to a first constellation point on a constellation graph and the second bit value corresponds to a second constellation point that is relatively closer to a center of the constellation graph than the first constellation point based on the second probability being greater than the first probability. The UE transmits the message including systematic bits modulated according to the asymmetric modulation rule.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) generates multiple systematic bits for a message, where the systematic bits are nonuniformly distributed over a time period such that a first bit value has a first probability of occurrence during the time period and a second bit value has a second probability that is greater than the first probability of the occurrence. The UE modulates the systematic bits according to an asymmetric modulation rule such that the first bit value corresponds to a first constellation point on a constellation graph and the second bit value corresponds to a second constellation point that is relatively closer to a center of the constellation graph than the first constellation point based on the second probability being greater than the first probability. The UE transmits the message including systematic bits modulated according to the asymmetric modulation rule.