RF&WirelessBlog

Avago debuts integrated switch and LNA Modules for TD-SCDMA and TD-LTE base stations at Baltimore

Avago Technologies debuted a new series of high-power switch low-noise amplifier (LNA) modules at the 2011 IEEE Microwave Theory & Techniques Society International Microwave Symposium at the Baltimore Convention Centre last week. The LNA modules are dedicated for use in front-end receiver designs of TD-SCDMA and TD-LTE base transceiver station (BTS) applications. The new small-footprint ALM-12x24 modules replace existing three-piece discrete solutions, providing significant board space savings that are especially critical for BTS designs with 8 transceiver channels in a single radio card. The fully-matched solutions also shorten design cycle time by eliminating the need for tuning with external matching circuitry. The modules deliver best-in-class noise performance, high-gain and high linearity from a compact package.

ADI data converters maximise receiver sensitivity and dynamic range for 3G/4G basestations

Analog Devices Inc. (ADI) has introduced four high-speed data converter products that support the signal sampling rates necessary to accommodate 3G/4G  multi-carrier radio platform requirements. The new introductions include the AD6649 and AD6643 IF diversity receivers and AD9643 and AD9613 high-speed A/D converters. All the products complement other receive-chain components to simplify control loops and maximise base station receiver sensitivity and dynamic range, says ADI.

Cellular reports highlight Chinese market growth in 2010

Two newly-published market studies – from Forward Concepts and Strategy Analytics – have provided a snapshot of different areas of the cellular market, and have both concluded that China promises strong growth prospects in 2010.

Basestation market up 10% in 2009, says In-Stat

The number of newly deployed macro cellular basestations worldwide has grown by over 10% during 2009, according to a newly published report by analysts In-Stat. The basestation market is thriving despite the poor state of the worldwide economy, and is being driven by demand for mobile phones, especially smartphones, and wireless broadband services. macro cellular basestations will grow over 10% in 2009.

ST-Ericsson and Ericsson achieve first handover between LTE and HSPA

Working in Stockholm – where TeliaSonera launched its first LTE network this week –  ST-Ericsson and Ericsson have reported the first successful data call handover between LTE and HSPA networks, using a multimode LTE/HSPA device powered by ST-Ericsson's M710 multimode platform. The companies describe this demonstration of a mobile broadband data call in an LTE network, and its successful handover to an HSPA network, as a further step towards the widespread deployment of LTE.

ST-Ericsson delivers first TD-HSPA modem chip samples in 65nm

ST-Ericsson and its Chinese subsidiary T3G have announced TD-HSPA modem chip samples in 65nm, said to be the first in the industry to use this geometry size. The new, smaller chip

Freescale introduces TD-SCDMA RF power devices and reference designs

Freescale Semiconductor is introducing two LDMOS RF devices for final-stage power amplification in Time Division Synchronous Code Division Multiple Access (TD-SCDMA) systems – these are being deployed throughout China and also currently under consideration for other regions.

Designers are being offered a choice between discrete and IC solutions. The MRF7P20040H is an LDMOS FET with 50W peak RF output power; drain efficiency of 43%; 18dB gain at 10W average output power; and air-cavity ceramic package with internal matching for ease of use. The MD7IC2050N is a multi-stage integrated power amplifier IC with 70W peak RF output power; drain efficiency of 35%; 29dB gain at 10W average output power; and on-chip quiescent current temperature compensation with 50Ω on-chip input matching in a moulded plastic package capable of withstanding 225 deg C. Values quoted are typical Doherty performance as measured with a six-carrier, 2025 MHz TD-SCDMA. Both devices are particularly well suited for use in Doherty amplifiers, which are currently used in basestation transceivers to maximise power efficiency.

The new LDMOS devices allow designers to optimise RF power amplifiers to their chosen design, either using a discrete, three-stage PA configuration with the MRF7P20040H as the final amplifier, or using the MD7IC2050N IC (which includes the driver and final amplifier stages) in a two-stage PA configuration.

At the same time Freescale is introducing two reference designs based on Doherty architecture, enabling manufacturers to rapidly create compact, cost-effective, high performance basestation transceiver products for TD-SCDMA networks.

A Doherty amplifier design normally incorporates two amplifiers for different signal amplitude levels, and typically use separate transistors for each amplifier. However, the new devices support a dual-path configuration, which allows a Doherty amplifier to be constructed using a single device rather than two for the final-stage amplifier. In addition, since both devices are inherently broadband, they can operate in both bands allocated for TD-SCDMA (1880 to 1920 MHz and 2010 to 2025 MHz), so that the same device can be used to provide RF power in both bands. These advantages combine to offer the potential for a significant reduction in size, bill-of-materials and circuit complexity for a TD-SCDMA amplifier, while also simplifying inventory management.

The two Doherty amplifier reference designs can significantly shorten the amplifier design cycle. The first design employs the MMG3014N general-purpose amplifier driving the MD7IC2050N to produce a two-stage IC-based amplifier that delivers 35% efficiency at 10W average RF output and a total gain of 45dB. The second design incorporates Freescale's MMG3014N as the pre-driver, the MW6S004N LDMOS FET as the driver and the MRF7P20040H as the final amplifier stage, resulting in a three-stage, discrete-based PA that delivers 38% efficiency at 10W average RF output and 50dB of total gain.