Abstract:
Methods, systems, and devices are described for wireless communication at a user equipment (UE). A UE may establish a connection with a cell based on an initial access procedure. The UE may also receive a downlink signal from the cell which includes a first cyclic prefix. The UE may transmit an uplink signal with a second cyclic prefix to the cell. The second cyclic prefix may have a different length than the first cyclic prefix.
Abstract:
Methods, systems, and devices are described for wireless communication at a UE. A user equipment (UE) may perform an initial access procedure to establish a connection with a serving cell. The UE may then arrange a regular transmission schedule with the serving cell including a discontinuous transmission (DTX) cycle and an acknowledgement schedule. The UE may enter a low power mode and refrain from any transmission during the a sleep interval of the DTX cycle. The UE may then wake up and transmit a message to the serving cell after the sleep interval without performing another access procedure. The UE may perform another access procedure to transmit at times not covered by the regular transmission schedule. For example, if an acknowledgement (ACK) for the message isn't received, the UE may perform another access procedure for retransmission.
Abstract:
Methods, systems, and devices are described for wireless communication at a user equipment (UE). In some examples, a base station may allocate, to a UE, time and/or frequency resources for transmitting physical random access channel (PRACH) signals. The resource allocation may be apportioned based on a type and class of PRACH signal. For instance, a UE may be assigned a first subset of resources to transmit regularly scheduled traffic and a second subset of resources to transmit on-demand traffic. Regularly scheduled traffic may include, for example, sensor measurements reported to the base station on a predetermined time interval (e.g., 24 hour time interval). In contrast, an on-demand traffic may include an impromptu transmission, initiated based on a detection of at least one reporting trigger (e.g., sensing an abnormality at the UE).
Abstract:
A method, an apparatus, and a computer program product for wireless communication are provided. According to one embodiment, a method of operating a device includes: selecting a signal format from a plurality of signal formats, each of the plurality of signal formats corresponding to a respective coding and modulation scheme of a plurality of coding and modulation schemes; and sending a request for random access to a base station according to the selected signal format.
Abstract:
Methods, systems, and devices are described for wireless communication at a UE. A user equipment (UE) may utilize orthogonal frequency division multiple access (OFDMA) for demodulating downlink messages and a combination of Gaussian minimum shift keying (GMSK) and single carrier frequency division multiple access (SC-FDMA) for uplink modulation. The uplink modulation process may include generating a symbol vector with an M-point discrete Fourier transform (DFT), filtering the symbol vector with a frequency domain Gaussian filter, generating a sample vector from the filtered symbol vector utilizing an inverse DFT, and modulating the sample vector utilizing GMSK. In some cases, the uplink modulation may be based on a narrowband resource allocation received from a base station.
Abstract:
Methods, systems, and devices are described for wireless communication at a user equipment (UE). A UE may establish a connection with a cell based on an initial access procedure. The UE may also receive a downlink signal from the cell which includes a first cyclic prefix. The UE may transmit an uplink signal with a second cyclic prefix to the cell. The second cyclic prefix may have a different length than the first cyclic prefix.
Abstract:
Methods, systems, and devices are described for wireless communication at a user equipment (UE). A UE may establish a connection with a cell based on an initial access procedure. The UE may also receive a downlink signal from the cell which includes a first cyclic prefix. The UE may transmit an uplink signal with a second cyclic prefix to the cell. The second cyclic prefix may have a different length than the first cyclic prefix.
Abstract:
Systems and methods are disclosed that may determine phase offsets in wireless devices. In accordance with some embodiments, a phase of a local oscillator signal associated with transmission of data from a wireless device may be measured by generating a reference signal having a frequency that is a selected integer value times a frequency of a baseband clock signal, generating the local oscillator (LO) signal to have a frequency substantially equal to a carrier frequency of the data transmission, and mixing the reference signal and the LO signal to generate a mixed signal indicative of the phase of the LO signal.
Abstract:
To enable efficient synchronization and/or cell acquisition, systems and methods are described for broadcast of a synchronization signal in a synchronization channel. According to an aspect, a base station may generate a synchronization signal and assign the synchronization signal to be carried on a synchronization channel that is time-division multiplexed with one or more other channels (e.g., one or more other downlink channels). The synchronization channel may be a single-carrier channel and/or a wide-band channel. The base station may transmit synchronization signal (e.g., periodically broadcast) on the synchronization channel to enable a time and/or frequency synchronization. According to an aspect, the UE may acquire synchronization information based on detection of the repeating synchronization signal.
Abstract:
Methods, systems, and devices are described for wireless communication at a user equipment (UE). A UE may synchronize with a cell using a waveform known to the UE beforehand, and common to a group of cells. The UE may determine a physical broadcast channel (PBCH) time. The UE may receive the PBCH and determine a physical layer identification (ID) for the cell and a frequency for uplink transmissions. The PBCH may also indicate a channel configuration, which may enable the UE to perform a random access procedure. The channel configuration may include a time/frequency resource configuration of a shared traffic channel. In some cases, the UE may determine resources for data transmission based on an index of a control channel transmission. In some cases, there may be a predetermined delay between control channel transmissions and data channel transmissions. The UE may then enter a low power state during the delay.