Abstract:
A CDMA communication system includes a signal processor which encodes voice and nonvoice signals into data at various rates, e.g. data rates of 8 kbps, 16 kbps, 32 kbps, or 64 kbps as I and Q signals. The signal processor selects a specific data rate depending upon the type of signal, or in response to a set data rate. When the signal is received and demodulated, the baseband signal is at the chip level. Both the I and Q components of the signal are despread using the conjugate of the pn sequence used during spreading, returning the signal to the symbol level. Carrier offset correction is performed at the symbol level. A lower overall processing speed is therefore required.
Abstract:
A wireless transmitter comprises an input configured to receive a data signal. A mixer mixes the data signal with a correction signal producing a corrected signal. The correction signal changes a phase in the data signal to compensate for a measured phase error at a desired receiver. A modulator modulates the corrected signal to radio frequency as a radio frequency signal. An antenna radiates the radio frequency signal.
Abstract:
A digital spread spectrum communication system calculates phase and frequency error on a received signal from a communicating entity during a wireless communication and pre-corrects a signal for phase and frequency error prior to transmission to that entity.
Abstract:
The present invention is a method and apparatus for reducing transmission errors by a user equipment (UE) when transmitting a communication signal. An RF communication signal is received at the UE and analyzed for errors. A correction signal is then generated based upon the analysis. Prior to transmission of the communication signal from the UE, the communication signal is corrected using the correction signal.
Abstract:
A CDMA communication system includes a signal processor which encodes voice and nonvoice signals into data at various rates, e.g. data rates of 8 kbps, 16 kbps, 32 kbps, or 64 kbps as I and Q signals. The signal processor selects a specific data rate depending upon the type of signal, or in response to a set data rate. When the signal is received and demodulated, the baseband signal is at the chip level. Both the I and Q components of the signal are despread using the conjugate of the pn sequence used during spreading, returning the signal to the symbol level. Carrier offset correction is performed at the symbol level. A lower overall processing speed is therefore required.
Abstract:
A wireless transmitter comprises an input configured to receive a data signal. A mixer mixes the data signal with a correction signal producing a corrected signal. The correction signal changes a phase in the data signal to compensate for a measured phase error at a desired receiver. A modulator modulates the corrected signal to radio frequency as a radio frequency signal. An antenna radiates the radio frequency signal.
Abstract:
The present invention is an apparatus for reducing transmission errors by a base station when transmitting a communication signal. An RF communication signal is received at the base station and analyzed for errors. A correction signal is then generated based upon the analysis. Prior to transmission of the communication signal from the base station, the communication signal is corrected using the correction signal.
Abstract:
In one disclosed embodiment, data information is stored in a buffer in a transmitter. The data information is transmitted on a shared channel and control information for recovering the associated data information is transmitted on a dedicated channel. The shared and dedicated channels can be, for example, different portions of the frequency band. The control information can include a spreading factor used to spread the data at the transmitter. For example, the spreading factor can be the length of the Walsh function orthogonal coding used to spread the data. The control information is received over the dedicated channel before the associated data information is received over the shared channel. The control information is then used to recover the associated data information. For example, knowing the spreading factor from the control information, the correct Walsh function can be selected to de-spread, i.e. to Walsh de-cover, the data information.
Abstract:
The present invention is an apparatus for reducing transmission errors by a user equipment (UE) when transmitting a communication signal. An RF communication signal is received at the UE and analyzed for errors. A correction signal is then generated based upon the analysis. Prior to transmission of the communication signal from the UE, the communication signal is corrected using the correction signal.
Abstract:
The present invention is designed to reduce the decrease of spectral efficiency even when repetitious transmission is applied to communication by user terminals, in which the band to use is limited to a partial narrow band in a system band. According to one aspect of the present invention, a user terminal, in which the band to use is limited to partial narrow bands in a system band, has a receiving section that receives information related to spreading codes, a generation section that generates uplink signals, and a transmission section that repeats transmitting uplink signals in a plurality of subframes, and the generation section applies a predetermined spreading code to an uplink signal that is transmitted in part or all of the plurality of subframes, based on the information related to spreading codes.