Transmission method

Patent metadata

Field	Value
Publication number	US-9491026-B2
Application number	US-201414781455-A
Country	US
Kind code	B2
Filing date	Apr 10, 2014
Priority date	Apr 12, 2013
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

Provided is a transmission method that contributes to an increase in data reception quality when iterative detection is performed at a receive apparatus side. A transmit apparatus alternates between two types of modulation scheme that each shift amplitude and phase, performs mapping to constellation points according to a selected modulation scheme, and transmits a modulated signal obtained by mapping.

First claim

The invention claimed is:

1. A transmit apparatus for transmitting data by modulation schemes that shift amplitude and phase, the transmit apparatus comprising:
a selector that selects a first modulation scheme or a second modulation scheme for each symbol in order, alternating between the first modulation scheme and the second modulation scheme, a constellation and bit labelling of each constellation point of the first modulation scheme being different to a constellation and bit labelling of each constellation point of the second modulation scheme;
a mapper that performs mapping by using constellation points of a selected modulation scheme; and
a transmitter that transmits a modulated signal obtained by the mapping, wherein
the first modulation scheme is 16 amplitude phase shift keying (APSK) modulation that arranges, in a first in-phase (I)-quadrature-phase (Q) plane, 16 constellation points composed of four constellation points on the circumference of a first inner circle and twelve constellation points on the circumference of a first outer circle, the first inner circle and the first outer circle being concentric circles, wherein:
when the 16 constellation points are divided into four groups each composed of one constellation point on the circumference of the first inner circle and three constellation points on a portion of the circumference of the first outer circle in a direction from the origin of the first I-Q plane to the one constellation point,
only one bit is different in bit labelling between each pair, within each group, of constellation points adjacent on the circumference of the first outer circle, and only one bit is different in bit labelling between each pair, within each group, of each constellation point on the circumference of the first inner circle and each constellation point at one of two ends of each portion of the circumference of the first outer circle; and
only one bit is different in bit labelling between each pair, between different groups, of constellation points that are closest to each other on the first I-Q plane on the circumference of the first outer circle, and only one bit is different in bit labelling between each pair, between different groups, of constellation points that are closest to each other on the first I-Q plane on the circumference of the first inner circle, and
the second modulation scheme is 16APSK modulation that arranges, in a second I-Q plane, 16 constellation points composed of eight constellation points on the circumference of a second inner circle and eight constellation points on the circumference of a second outer circle, the second inner circle and the second outer circle being concentric circles, wherein:
when the 16 constellation points are divided into a first group composed of the eight constellation points on the circumference of the second inner circle and a second group composed of the eight constellation points on the circumference of the second outer circle,
only one bit is different in bit labelling between each pair, within the first group, of constellation points that are adjacent on the circumference of the second inner circle, and only one bit is different in bit labelling between each pair, within the second group, of constellation points that are adjacent on the circumference of the second outer circle.

2. The transmit apparatus of claim 1 , wherein
in the second modulation scheme, phases of the constellation points on the circumference of the second inner circle and phases of the constellation points on the circumference of the second outer circle are aligned.

Assignees

• Panasonic Ip Corp America
• Sun Patent Trust

Inventors

• Murakami Yutaka
• Kimura Tomohiro
• Ouchi Mikihiro

Classifications

• H04L27/34 Primary

  Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems · CPC title

• H04L27/0008 Primary

  arrangements for allowing a transmitter or receiver to use more than one type of modulation (negotiating modulation type for two-way transmission paths H04L5/1453) · CPC title

• H04W28/0263

  involving mapping traffic to individual bearers or channels, e.g. traffic flow template [TFT] · CPC title