Abstract: Precision synchronization is key to reliable communications at the high frequencies planned for 5G and 6G. A timing reference signal can provide a compact, resource-efficient, low-complexity phase noise mitigation while also providing an amplitude noise calibration. The timing reference signal is a QAM (quadrature amplitude modulation) signal with an I branch multiplexed with an orthogonal Q branch, in which one of the branches is modulated according to a maximum amplitude level of the modulation scheme, and the other branch has zero amplitude as-transmitted. When received, the amplitude and phase may be altered by noise. The receiver can measure the overall magnitude of the received I and Q signals to mitigate amplitude noise, and can also calculate a phase rotation angle according to a ratio of the I and Q branch signals as-received, and thereby correct for phase noise in the message.

Abstract: Currently, user devices in a 5G/6G wireless network must perform a complex iteration procedure to align their directional transmission/reception beams toward the base station. Disclosed is a faster, simpler procedure to enable users with beamforming capability to align their beams. The base station transmits a series of sequential signals, all with the same amplitude, modulation, and spatial distribution. A user device can receive the signals using directional reception beams oriented in various directions, measuring the signal quality for each of the reception beams. The user device can then select the reception beam with the best signal quality, or it can interpolate between the two best beams to determine the optimal alignment direction toward the base station. A single user device (such as a new arrival) can align its beam, or all of the user devices in the network can optimize their beams simultaneously, saving time at very low resource cost.

Abstract: In 5G and 6G, beam alignment remains an arduous, time-consuming process. Procedures are disclosed herein for rapid and efficient beam alignment, by configuring a phased-array antenna to emit a “triangular beam”, which is a wide beam that varies in angle from a high power at angle-1 to a low power at angle-2, with a ramp-like intensity variation in the region between the two angles. Then a second signal is emitted, with the triangular distribution reversed (higher power at angle-2). A receiver can then measure the as-received amplitudes from the two triangular beams, calculate the ratio of signal reception from the two beams, and thereby determine the alignment angle. In another version, the transmitter transmits two non-directional pulses, and the receiver detects them using a triangular sensitivity distribution versus angle. By either method, the devices can align their beams using just two triangle beam pulses, saving substantial time, resources, and background generation.

Abstract: As 5G, and especially 6G, push into ever-higher frequencies, phase noise presents an increasing problem. Disclosed are procedures and modulation schemes to mitigate phase noise and permit messaging at higher frequencies. Each modulation scheme provides phase-noise immunity by configuring modulation states with large phase acceptance regions. A message element is faulted if its sum-signal amplitude or phase is in an exclusion zone. Modulation schemes with fewer phase levels, more amplitude levels, and very broad phase acceptance regions are necessary for high frequency operation where phase noise dominates. Using allowed states with the maximum amplitude modulation in both branches can provide nearly 90-degree phase acceptance. Requiring that the two branches be equal provides nearly 180-degree phase acceptance. Further requiring that the amplitude levels be positive can provide total phase-noise immunity, with a 360-degree allowable phase range.

Abstract: A new user seeking a base station to join must first implement a grueling series of complex steps, which may be especially challenging for the majority of devices expected in next-generation 5G and 6G systems. If the user has a real emergency, such as an imminent traffic collision, then the time wasted in locating (“discovering”) a nearby base station and finally logging on may make the difference between life and death. Disclosed herein are procedures for new users to transmit a “hailing” message on an allocated frequency that multiple base stations continuously monitor. The base stations can then reply at a standard amplitude, so that the new user can determine which base station is closer (or provides the best signal reception) according to the received amplitude. In addition, the reply messages can include a characteristic frequency of the replying base station, such as its entry frequency.

Abstract: Disclosed are short-form demodulation reference signals configured to indicate certain modulation levels of a modulation scheme, from which a receiver can measure phase noise and amplitude noise in 5G/6G. A key feature of short-form demodulation references is resource efficiency. Examples include a demodulation reference occupying just one resource element, while providing the information needed to determine all of the modulation states of the modulation scheme, as well as the current noise factors. In one embodiment, the short-form demodulation reference may include two component signals with orthogonal phase, both being amplitude modulated by the transmitter according to a maximum amplitude level. The receiver can determine the phase noise from a ratio of the two received signal amplitudes, and the amplitude noise from the magnitude of the received waveform, thereby mitigating both amplitude noise and phase noise.

Abstract: Polling to determine which user devices wish to transmit, is a time-consuming and resource-intensive process in 5G and 6G. Procedures disclosed herein can provide a fast, extremely compact sequence whereby the base station can determine which users are ready to transmit. First, the base station divides the users into a number of sections, and assigns each user a position in its section. Then, in a “section poll”, the user devices indicate which sections include at least one ready user, and the base station broadcasts a terse listing of these section numbers. Then, in a subsequent “user poll”, the ready users specifically identify themselves, with another compact format. For example, the section poll may use just a single resource element per section, and the user poll may include only those sections that have at least one ready user. These resource-efficient protocols can thereby save energy and time while minimizing background generation.

Abstract: With rapid increases in the number and spatial density of wireless messages as 5G and 6G are rolled out, it is essential that improved methods for fault-tolerant demodulation and error mitigation be developed. Disclosed herein are methods for receiving a message concatenated with a demodulation reference, determining the predetermined modulation levels of a modulation scheme, and demodulating the message by measuring the amplitude mad/or phase modulation values of each message element. The measured modulation values are then compared with the predetermined modulation levels of the modulation scheme to demodulate the message. Importantly, the message can be demodulated by determining an amplitude and phase of the raw signal for each message element, or by separating the raw signal into two orthogonal “branches” and determining the amplitudes of the two branches. By demodulating the message both ways, message faults may be identified and mitigated, according to some embodiments.

Abstract: In current practice, faulted messages are typically discarded and a retransmission is requested. Forward error-correction codes (FEC) in 5G and 6G are bulky, resource-expensive, and often unable to resolve the problem. Disclosed are systems and methods for determining which specific message elements are faulted, so that just the faulted portion can be retransmitted, instead of the entire message. For example, the amplitudes of the I and Q branches, of each message element, can be compared to the calibrated amplitude levels of the modulation scheme. Any message element with a large amplitude deviation is suspect. Other factors, such as the SNR, can also be considered in evaluating the validity of each message element. Usually, all of the faulted message elements occupy just a portion of the message. Compact formats are disclosed specifying which portion of the message is to be retransmitted, thereby saving time, power, and background generation.

Abstract: A base station of a 5G/6G network can include its location coordinates in the SSB system information message which is broadcast on a standard frequency periodically. A mobile user device can receive the SSB and thereby determine the base station location. Thereafter, the user device can measure its own location, speed, and direction of travel, and thereby calculate a Doppler frequency correction before transmitting a message to the base station, thus causing the base station to receive the message at the expected standard frequency. In addition, the user device can calculate, based on the location of the base station relative to the direction of travel of the mobile user device, a particular frequency at which downlink messages from the base station will be received. In addition, the user device can pre-emptively adjust its transmission frequency when changing speed or direction, thereby avoiding wasteful frequency-correction messages from the base station.

Abstract: To mitigate phase noise and amplitude noise in a 5G or 6G message, the transmitter can include an extremely compact demodulation reference with a predetermined format including a first branch and an orthogonal second branch. The first branch can exhibit the maximum positive amplitude level of the modulation scheme, and the second branch can exhibit either the minimum positive level or the maximum negative level, depending on implementation. The receiver can determine, from the received branch amplitudes, a phase correction and an amplitude correction. Upon receiving a message including noise, the receiver can calculate a sum-signal amplitude and sum-signal phase according to the branch amplitudes of each message element, subtract the amplitude correction and phase correction, derive corrected branch amplitudes, and compare them to the predetermined amplitude levels of the modulation scheme. The receiver can thereby demodulate the message element with the phase noise and amplitude noise largely negated.

Abstract: At high frequencies planned for 5G and 6G, phase noise may be a limiting factor on reliability and throughput. The default modulation scheme is currently QAM. Disclosed is a more versatile demodulation method based on the amplitude and phase of the sum-signal, which is the vector sum of the two branch amplitudes of QAM. The transmitter modulates a message by sum-signal amplitude and phase. The receiver can process the received waveform according to quadrature branches as usual, and determines the branch amplitudes. The receiver then calculates, from the branch amplitudes, the sum-signal amplitude and sum-signal phase for demodulation. The receiver can thereby obtain substantially enhanced phase-noise tolerance and amplitude spacing uniformity at virtually no cost. In addition, methods are disclosed for determining specific message fault types and non-square modulation tables depending on the type of mitigation required.

Abstract: For improved messaging reliability in 5G and 6G, mobile users and their base stations can adjust their transmission power according to the current location of the mobile user. Each entity can maintain a map of known attenuation values, including “dead zones”, and can adjust their transmission power and/or reception gain to compensate. Instead of constantly exchanging location-update messages, the users can indicate their speed and direction, and the base station (or other users) can extrapolate the location versus time to determine a future location, and thereby determine the attenuation factor at the new position. In addition, the base station can use a map to follow the mobile user device's progress, and can thereby update the attenuation factor in real-time. If the mobile user makes a change, it can inform the base station at that time, or during initial access. Result: improved reliability, lower energy consumption, improved traffic safety.

Abstract: With increasingly dense wireless traffic in 5G and 6G networks, the incidence of message faults due to interference is increasing, leading to wasted time and energy on multiple re-transmissions. Disclosed are procedures for assembling a fault-free copy of a message from two corrupted copies. First, measure the modulation quality of each message element. A faulted message element usually has poor modulation quality. Then, select the best message elements from each of the two corrupted copies, and test the merged version against an embedded error-detection code. If the merged copy still fails the test, select each of the message elements that are different in the two faulted copies since they are all suspicious, and test each version with the error-detection code. By recovering a message despite reception errors, another transmission is avoided, saving time and energy, and avoiding contributing yet further to the background noise. Many additional aspects are disclosed.

Abstract: A method is disclosed for mitigating phase noise at high frequencies in 5G and 6G. Quadrature modulation schemes, in which orthogonal branches are amplitude modulated, are susceptible to phase noise which rotates the branches, causing demodulation faults. Disclosed is a single-branch reference signal that can mitigate phase noise. The transmitter can transmit a particular resource element having a normal amplitude in one branch, and zero amplitude in the orthogonal branch. The receiver can then measure the amplitudes of the particular resource element as-received (with phase noise), and determine a phase rotation angle according to a ratio of the two branch amplitudes. The receiver can then correct the branch amplitudes of each message element, and thereby negate the effect of the phase noise. The disclosed procedures can thereby make high-frequency, high-reliability communication feasible, at extremely low cost.

Abstract: 5G and especially 6G will enable a multitude of applications for fixed-position and mobile wireless task-devices (“robots”). Most of these applications are based on the assumption that the robots know, or can determine, the locations and wireless identities of other robots in proximity, but this is an unsolved problem. Procedures are provided herein for an arbitrarily large number of fixed-position and mobile robots to autonomously identify each other, determine their locations with speed and precision substantially beyond that provided by navigation satellites, and then to collaborate in performing their tasks, while avoiding interference and collisions. Examples are provided in the fields of automated agriculture, remote oil-spill mitigation, autonomous fire-fighting, hospital management, construction site coordination, manufacturing (including fully autonomous manufacturing), major product warehousing, airport control, and emergency vehicle access.

Abstract: Mobile devices, autonomous sensors and actuators, and myriad other IoT wireless devices demand low-complexity protocols in addition to 5G and 6G protocols. Disclosed are methods for devices to form spontaneous local sidelink networks without involvement of a base station. In a first aspect, a user device can broadcast a hailing message soliciting replies from all devices in range, each reply including the wireless address of the replying user device. In another aspect, each of the user devices in a sidelink network can periodically transmit a semaphore message indicating its wireless addresses, and a new arrival can join the sidelink network by appending its semaphore message to the others. After forming the sidelink network, the user devices can communicate among themselves unicast (addressed to a specific member of the sidelink network). Also disclosed are procedures for recovery from message collisions and transmission of emergency messages. Many other aspects are disclosed.

Abstract: An improved way is disclosed for recovering a message by merging two corrupted copies of the message in 5G or 6G. Message faults, from noise or interference, distort the modulation of one or more message elements. In a modulation scheme of amplitude-modulated quadrature (I and Q) signals, noise can change the amplitude values, which results in demodulation faults. Often the reception is so poor that a retransmission of the message is also faulted. Nevertheless, the receiver can recover the correct message by measuring a modulation quality of each message element, and assembling a merged message from the best-quality message elements of the two copies. The modulation quality depends on the message element's amplitude versus the calibrated amplitude levels of the modulation scheme. By selecting the individual message elements from the two faulted copies, based on the modulation quality, users can obtain better reception at longer distances while expending less power.

Abstract: In 5G and 6G, a user device is expected to perform an arduous blind search in each downlink control space to detect its DCI (downlink control information) messages. To save energy and complexity, especially for reduced-capability IoT applications, low-complexity procedures are disclosed that enable each user to request a custom search-space comprising one or more specific times and frequencies. Each downlink control or data message then starts in the custom search-space. The data or control messages may include the user's ID code, in plain text (as opposed to complex encoding) and/or the length of the message, so that the user can readily identify its messages. The user device may thereby readily separate its messages from the stream of incoming data. Result: saved time and energy, fewer dropped messages, and generally improved network performance, especially for simpler processors and devices.

Abstract: Disclosed are methods for base stations to indicate the start and end of a downlink message, by prepending and appending demarcations to the message in 5G or 6G. A user device can then readily locate the message by detecting the demarcations, greatly reducing the amount of computation required of the receiver processor. There may be no need for a DCI message alerting the user device of the coming message. Each demarcation may be a brief predetermined bit sequence such as a demodulation reference or an identification code of the intended recipient. The start and end demarcations may be different, and may include a gap of zero or low transmission, to further assist the receiver. The user device may transmit a request message to the base station, requesting that demarcations be applied to the user's downlink messages, and declining the redundant DCI alert messages, thereby saving further energy and network overhead.