39 results about "Spatial division multiplexing" patented technology

A wireless base station device includes a plurality of transmit weight generation sections and a beam selection section. The transmit weight generation sections generate pieces of transmit weight information used for spatial division multiplexing transmission according to different algorithms. The pieces of transmit weight information are generated based on channel information on a plurality of terminals each having one or more antennas with which the wireless base station device performs spatial division multiplexing transmission. The beam selection section selects one of the pieces of transmit weight information generated.

The invention discloses a sensing device based on Raman-Brillouin distributed temperature and stress dual-parameter detection. The sensing device is composed of a laser, a first coupler, a polarization controller, a pulse generator, a semiconductor optical amplifier, an erbium-doped fiber amplifier, a band-pass filter, a second coupler, an optical attenuator, a first circulator, a third coupler, a multi-core fiber, a second circulator, a Raman filter, a first d photoelectric detector, a second photoelectric detector, an oscilloscope, a polarization controller, a modulator, a microwave generator, a polarization switch, a fourth coupler, a third photoelectric detector, a power spectrum analyzer and a data processing module. Because a spatial-division multiplexing system is formed by using a single-mode multi-core fiber, a problem of mode coupling of a mode -division multiplexing system and power mismatching of a wavelength-division multiplexing system can be solved and thus an effect of precise and simultaneous temperate and stress obtaining can be realized.

The reception (102) reception unit includes; a first processing unit processing a first signal received from a source channel, and including a filtering unit to filter said first signal in digital domain, and extract unit to extract a information from said first signal; a second processing unit processing a second signal received from a destination channel, and said source channel and said destination channel are distinct each other; a third processing unit providing said information extracted from said first signal to said second signal said third processing unit executes; providing said information from said first processing unit to said second processing unit using information lanes of a clock rate strictly lower than a symbol rate of said second signal, a monitoring unit to generate a monitor signal according to the quality of said second signal; and a control unit controlling a skew between said first signal and said second signal in a bandwidth of said filtering units in said first processing unit.

In a wireless network employing Spatial Division Multiplexing Access (“SDMA”) in at least one of its cells, a method is provided for dynamically allocating transmission resources to different subscriber devices. The method comprises the steps of: providing at least one base station comprising at least one antenna array; providing one or more sectors associated with that wireless communications network; dynamically dividing one or more of the sectors into a plurality of virtual sub-sectors, each allowing communications between the base station and at least one respective subscriber; from among the plurality of the virtual sub-sectors, selecting at least one pair of subscriber devices wherein each of the pair of subscriber devices is not interfered substantially by transmissions directed to the other subscriber of that pair; for each of the divided sectors, generating plurality of time frequency allocation maps; transmitting the generated maps to all virtual sub-sectors associated with the respective sector; and for each of the sectors, beamforming the transmissions to be conveyed to the subscriber devices' pairs, summing them and conveying the summed result towards the array antenna.

An optical data transmitter includes vertical cavity surface-emitting lasers and an all-optical spatial mode multiplexer. Each vertical cavity surface-emitting laser is configured to output a data modulated optical carrier at a center wavelength of less than one micrometer. The all-optical spatial mode multiplexer has an optical output and optical inputs. Each vertical cavity surface-emitting lasers is optically connected to one or more of the optical inputs of the all-optical spatial mode multiplexer. The all-optical spatial mode multiplexer is configured to cause at least two of the vertical cavity surface-emitting lasers to excite linearly independent combinations of one or more optical spatial propagating modes of an optical fiber in response to the optical output being coupled to a near end of the optical fiber.

The invention discloses a distributed fiber coupling biochemistry sensor and corresponding fiber link circuit and sensing system. The inventive sensor as basic sensing unit of sensing system comprises a long period fiber grating, Bragg fiber grating and absorbing or sensing film for chemical or biochemical molecule; a plurality of such basic sensing unit connected serially with sequence and direction forming the fiber link circuit. Sensing system comprises the fiber link circuit and broad band light source, broad band coupler, initial Bragg fiber grating, fiber light spectrum demodulator and computer. The invention is characterized in that it takes wavelength-division multiplex to realize distributed sensing and has the advantages of simple and reliable.

A receiver for a hybrid space time block codes (STBC) scheme using a nonlinear decision feedback (DFB) filter instead of a conventional linear filter which are used in the hybrid STBC scheme, that is, a combination of a spatial division multiplexing (SDM) scheme and a STBC scheme. In the receiver used for the STBC scheme, a previous-stage remaining signal is detected by using a well-known BLAST algorithm, and inter-symbol interference (ISI) is minimized by applying the previous-stage remaining signal to a current-stage signal, providing improved performance. The receiver used for the STBC scheme can be applied to a time varying channel fading environment as well as a quasi-static channel environment. According to the hybrid STBC scheme, a gain of about 3 dB can be obtained in channel environments having a frame error rate (FER) frequency efficiency of 2 and 3 Bps/Hz in the same condition by using a simulation.

The present invention relates to multiple antenna wireless access points that multiplex signals by spatial division. In particular, it relates to grouping clients of the access point for spatial division multiplexing. Particular aspects of the present invention are described in the claims, specification and drawings.

The invention discloses a low-crosstalk weakly-coupled spatial division multiplexing fiber, which relates to the field of communication fibers. The low-crosstalk weakly-coupled spatial division multiplexing fiber comprises a multi-core fiber cladding layer; the multi-core fiber cladding layer comprises multiple few-mode fibers which are arranged hexagonally or in other axial symmetry modes; the number of the few-mode fibers is no smaller than 3; and the few-mode fiber comprises a few-mode core area, an inner cladding layer and a depressed cladding layer sequentially arranged from inside to outside. The spatial division multiplexing fiber adopts the weakly-coupled few-mode fiber core area and the low-crosstalk multi-core fiber structure, channels between the core areas inside the whole fiber and channels between modes in the core areas are completely separated, a multiplexing/demultiplexing technology is matched at input and output ends to complete link communication transmission, the whole transmission capacity of the fiber is effectively enhanced, and the transmission quality is high.

In the present invention, by providing a 3D holographic display system comprising a modulation apparatus configured to modulate light emitted from a light source into a light wave corresponding to a 3D image, an optical apparatus configured to propagate the light wave into the first plane, and a diffraction apparatus configured to multiplex the propagated light wave to extend viewing angle of the 3D holographic display, a limited viewing zone of the holographic display determined by the SLM pixel pitch, may be extended by optical methods, such as using diffractive optical elements (DOE) for spatial-division multiplexing (SDM).

A space-division multiplexed optical fiber includes a relatively high refractive index optical core region surrounded by alternating regions of relatively low and relative high refractive index material, forming concentric high index rings around the core. The optical core region supports propagation of light along at least a first radial mode associated with the optical core region and a high index ring region supports propagation of light along at least a second radial mode associated with the high index ring region. The second radial mode is different from the first radial mode.

A communications system, comprising a transmitter and a receiver, are operable to communicate information using a spatial multiplexing method. The transmitter is operable to separate data to be transmitted into two categories, Alamouti encoding the symbols of the first category and transmitting them on an even number of antennae, and not encoding the second category of symbols, but merely using a modulation scheme such as QAM, and transmitting them on one or more further antennae. A corresponding receiver is operable to successively detect signal components received on corresponding spatially displaced antennae, and then to determine an estimated channel response from the signal components. A weighting function is then derived to extract a stream of data from the received signal, which, on the basis that the Alamouti STBC encoded signal will have the highest signal to noise ratio, will normally be the latter, while other data not encoded according to Alamouti is detected thereafter.

The invention provides a space division multiplexing method and a space division multiplexing device. The space division multiplexing method comprises the following steps: when one or more variable attribute downlink time slots are accessed to a second service, the time slot whose all time slot resources of the variable attribute downlink time slots are occupied by a first service is determined as a spacable division multiplexing time slot from the variable attribute downlink time slots carrying the first service, and whether the first service and the second service are paired successfully on the confirmed spacable division multiplexing time slot, if the pairing is succeeded, the spacable division multiplexing time slot with succeeded pairing is spaced and multiplexed, so that the first service and the second service can be transmitted synchronously through the spacable division multiplexing time slot. With the adoption of the method and the device, a space division carrier wave resource utilization rate is increased, and the cell downlink access is increased.