Motorola Corporation

Industrial Technology Research Institute

Ite Tech. Inc.

Integrated System Solution Corporation

Yumin Lee

Brian Keith Classon

Bruce D Mueller

Jeng-Hong Chen

Shih-Kai Lee

Joseph Michael Nowack

Arnauld Taffin

Min-Chen Ho

Yuh-Chun Lin

Karine Gosse

Sheng-Chung Lai

Yen-lun Chen

The disclosure provides an image capturing device and an image capturing method. The image capturing device includes a tone mapping circuit, a color correction circuit, and a color gamut mapping circuit. The tone mapping circuit obtains a first image including a first pixel and performs a tone mapping operation to obtain a brightness adjustment parameter, where the first pixel includes a plurality of first color channels. The color correction circuit converts the first color channels into a plurality of second color channels based on the brightness adjustment parameter and the brightness of the first pixel. The color gamut mapping circuit performs a color gamut mapping operation on the second color channels to convert the second color channels into a plurality of third color channels, and outputs a second image, where the second image includes the second pixel characterized by the third color channels.

Image capturing device and method

A quadrature frequency division multiplexing ('OFDM') wireless receiver, including methods and devices for adaptive quantization of OFDM signals according to modulation and coding schemes and sub-carrier frequency responses, is provided. Efficient quantization may be utilized to reduce the large dynamic range of signals to achieve circuit simplification and chip area reduction. In one embodiment, a quantization circuit includes a quantization selector to select quantization thresholds according to modulation and coding schemes and sub-carrier frequency responses, and a non-uniform quantizer to reduce input dynamic range so that an output is represented by fewer bits than an input.

Adaptive quantization method and apparatus for an OFDM receiver

A PAPR reduction method using bit reallocation is disclosed, which is applied in a multi-carrier system. The lowest total transmission power P is achieved by a bit loading algorithm conditioned on the requirement of total D transmission bits per block. When the PAPR (peak to average power ratio) of the block is larger than a predetermined value A, the bit reallocation is performed to add &#x394;d-bit transmitting data to one sub-carrier and subtract &#x394;d-bit transmitting data from another sub-carrier, thereby continuing bit reallocation until the PAPR meets with the system requirement or an iteration number reaches a predetermined maximal number of iteration L.

PAPR reduction method using bit reallocation

A baseband detector includes a complex differential detector, a constellation point computer, and a phase shift keying (PSK) decoder. The complex differential detector outputs complex values in response to digitized samples derived from a received baseband signal. The PSK decoder generates decoded bits representing information symbols by determining in minimum distance between the complex values and plural constellation points provided by the constellation point computer. The constellation point computer can adaptively generate the constellation points based on a training sequence of information symbols and their corresponding complex valued outputs from the complex differential detector. The baseband detector can be used for frequency shifting keying (FSK) and differential phase shift keying (DPSK) demodulation in direct conversion receivers (DCRs).

Apparatus and method for baseband detection

In a method for channel equalization a communications receiver receives an input data stream comprising modulation symbols. A reduced set sequence estimation algorithm produces intermediate hard decisions, based on the input data stream and on a channel reference, which are applied to a decision feedback filter in a feedback loop. Soft output sequences of emitted symbols are also produced, based on the input data stream, which are decoded, error-corrected and re-encoded. The error-corrected soft output sequences are iteratively applied to the decision feedback filter, such that a channel equalized received data stream is generated based on both the feedback soft output sequences and the intermediate hard decisions. An iterative decision-aided equalizer is also described. In this manner, errors corrected by the decoder are not re-introduced into the decision feedback filter, hereby reducing the effect of error propagation in decision-aided feedback equalizers.

Decision-aided equalizer

A first group of bits (,), e.g., header symbols/bits, are interleaved to form a first group of interleaved bits. A second group of bits (,), e.g., data symbols/bits, are interleaved to form a second group of interleaved bits. The first and second groups of interleaved bits are mapped to an information burst (,). The first and second groups of interleaved bits may be mapped to the information burst relative to a group of known symbols (,) forming a training sequence. A disadvantaged bit location, i.e., a bit location within the mapping having a relative high probability of incurring a bit error, is identified and an advantaged bit location, i.e., a bit location within the mapping having a relatively low probability of incurring a bit error, is identified. A first group bit from the first group of interleaved bits mapped to the disadvantaged bit location is remapped to the advantaged bit location while a second group bit from the second group of interleaved bits mapped to the advantaged bit location is remapped to the disadvantaged bit location.

Growing community of inventors

Taipei, Taiwan

Yumin Lee