Wireless communications systems and methods related to multiplexing uplink control channel signals from different users are provided. A first wireless communication device obtains an uplink control channel multiplex configuration indicating a first frequency spreading sequence and at least one of a second frequency spreading sequence or a first spatial direction. The first wireless communication device communicates, with a second wireless communication device, a first uplink control channel signal including a first reference signal and a first uplink control information signal in a frequency spectrum based on the uplink control channel multiplex configuration. The first reference signal is based on the first frequency spreading sequence and the first uplink control information signal is based on at least one of the second frequency spreading sequence or the first spatial direction.

An ultra-wideband pulse generator, for radio communication at frequencies of 2 to 11 GHz comprises an oscillator providing an output signal at carrier frequency F0 followed by a radiofrequency switching transistor and a control circuit controlling the gate of the transistor to turn it on for duration T corresponding to the desired duration of a UWB pulse. The control circuit is arranged to successively apply, during the same UWB pulse, a first gate voltage turning the transistor on with first internal resistance value for a first part of duration T, a second gate voltage that turns the transistor on with second internal resistance value, different from the first, for a second part of duration T. These internal resistances cause the oscillation to be attenuated differently for duration T of the pulse, allowing the spectrum of the pulse to maintain it within the spectral templates imposed by the radio communication standards.

Provided are multiuser communication methods and devices for Code Division Multiple Access (CDMA). N modulated symbols which are obtained by modulating a code block coded by a channel coder are acquired, where N is a positive integer more than or equal to 2. The N modulated symbols are spread according to N spread sequences with a specified length, and there may be at least two different spread sequences in the N spread sequences with the specified length. The spread modulated symbols are transmitted.

Provided are multiuser communication methods and devices for Code Division Multiple Access (CDMA). N modulated symbols which are obtained by modulating a code block coded by a channel coder are acquired, where N is a positive integer more than or equal to 2. The N modulated symbols are spread according to N spread sequences with a specified length, and there may be at least two different spread sequences in the N spread sequences with the specified length. The spread modulated symbols are transmitted.

A method for compensating for a signal error at a transmit end of an optical time domain reflectometer is provided. The method includes: detecting an actual signal sequence of a PN sequence sent by a transmitter to a measured optical fiber and an actual signal sequence of an optical signal and reflected back by the measured optical fiber and received by a receiver; obtaining a compensation value of the optical signal that attenuates in a process in which the optical signal is reflected by the measured optical fiber; computing an optical fiber attenuation curve function obtained through a current iteration; and determining, when determining that the optical fiber attenuation curve function obtained through the current iteration satisfies a given condition, performance of the measured optical fiber according to the optical fiber attenuation curve function obtained through the current iteration.

A two-phase approach to machine-type communications is provided. In a first phase, for activity detection, at least one symbol is transmitted using a long signature. During a second phase, for data transmission, information-carrying symbols are transmitted using a short spreading signature. Activity detection performance is enhanced through the use of a longer spreading signature.

Embodiments of the invention provide telecommunications methods that facilitate sharing of spreading codes. According to one of the embodiments, a first telecommunications apparatus first selects a plurality of second telecommunications apparatuses to share at least one spreading code. Then, the first telecommunications apparatus uses each of the at least one spreading code to perform spreading operations for the second telecommunications apparatuses by turns repetitively.

Embodiments of the invention provide telecommunications methods that facilitate sharing of spreading codes. According to one of the embodiments, a first telecommunications apparatus first selects a plurality of second telecommunications apparatuses to share at least one spreading code. Then, the first telecommunications apparatus uses each of the at least one spreading code to perform spreading operations for the second telecommunications apparatuses by turns repetitively.

A method of operating a transmitter (FIGS. 3A and 5A) is disclosed. The method includes receiving a sequence of data bits (DATA), wherein each data bit has a respective sequence number. A first data bit of the sequence is spread (508) with a first spreading code (504) determined by the sequence number (502) of the first data bit. A second data bit of the sequence is spread (508) with an inverse of the first spreading code (506) determined by the sequence number (502) of the second data bit. The first and second data bits are modulated (510) and transmitted (516) to a remote receiver.

A method of operating a transmitter (FIGS. 3A and 5A) is disclosed. The method includes receiving a sequence of data bits (DATA), wherein each data bit has a respective sequence number. A first data bit of the sequence is spread (508) with a first spreading code (504) determined by the sequence number (502) of the first data bit. A second data bit of the sequence is spread (508) with an inverse of the first spreading code (506) determined by the sequence number (502) of the second data bit. The first and second data bits are modulated (510) and transmitted (516) to a remote receiver.