Author Archives: richard wilson

Green Hills secures its RTOS for IoT

Green Hills secures its RTOS for IoT

Green Hills secures its RTOS for IoT

Green Hills Software’s latest release of its µ-velOSity real-time operating system (RTOS) has new security and safety features. It is designed as a small foot-print RTOS for IoT and low power devices.

The RTOS is designed to use a small number of CPU clock cycles and memory, requiring only 1.6kbyte of ROM. This supports fast booting without the need for slower off-chip memory.

There is also support for new processor architectures including new family members from ARM Cortex-M and Cortex-R, and Power Architecture e200 processors.

There are also secure communications protocols SSL/TSL and SSH from Green Hills.

The company also offers a suite of FIPS 140-2 compliant cryptographic toolkits for developing high assurance data protection on microcontrollers.

The RTOS has been optimised for reduced interrupt service routine and context switching execution times, while hardware floating-point support for multi-tasking has been expanded.

“Developers can analyze and predict stack usage to avoid overflows – a safety and security hazard – especially important on memory-constrained microcontrollers,” said Green Hills.

Communication option include CAN, USB, TCP/IP, SD Card, Bluetooth and flash file systems.

 

Richard Wilson

Five things you should know about AI and robots

From de-politicised drones to intelligent vacuum-cleaners and AI, this could be the future of robotics described in five technology predictions, writes Simon Holt.

Industrial-standard robotic components, assembled with the most basic simulcrum of a face invites interaction

Industrial-standard robotic components, assembled with the most basic simulcrum of a face invites interaction

Robots have a bit of a mixed reputation in the media. One minute they’re vacuum cleaning our homes and delivering our pizzas, the next they’re stealing our jobs and threatening to take over the world.

Thanks to more than 100 years of science fiction books and TV shows, robots remain controversial: they’re either destined to save the planet, or doomed to destroy it.

But how much of this rhetoric is true? With more than 8.6 million robots in existence, and the field of robotics recently being pegged as the “fastest growing industry in the world”, we find ourselves increasingly wondering what this robot-overrun future will look like.

Are robots to be feared, or embraced? More importantly, what is a robot? Should we be counting automated vacuum cleaners and self-service checkouts as part of the new robotics revolution, or are these simply more examples of the ever-expanding internet of things (IoT)?

In an attempt to answer some of these questions, I undertook a review of the most revolutionary robotics developments expected to appear in hospitals, shop floors and workplaces.

The five key predictions for the next five years are outlined below, along with the core challenges they present to the industry, and the areas to watch for the future direction of robotics.

1. Design will bridge the uncanny valley

The so-called ‘uncanny valley’ refers to an aesthetic hypothesis which states that when features look and move almost – but not exactly – like natural beings, the typical response is one of discomfort, or even revulsion.

In response to this hypothesis the production of robotics has focused far more on the development of autonomous machines than on ‘humanoid’ robots.

While it seems unlikely that human beings will ever conquer this response, humanoid aesthetics are nevertheless increasingly vital to the success of many upcoming robotics projects.

As robots increasingly replace workers in a variety of service and social contexts (hospitals and care homes, for example) the need for anthropomorphic features will become increasingly important.

Social technologist Sherry Turkle claims that “a robotic face is an enabler; it encourages us to imagine that robots can put themselves in our place and that we can put ourselves in theirs”.

Based on this growing demand for “lifelike” robots, it is increasingly important that developers overcome the uncanny valley effect.

To achieve this robotic engineers will increasingly turn to semi-humanoid developments, which maintain a traditional machine form, while also boasting very basic – even cartoonish – human features.

A recent example is Baxter, a newly launched robot from Boston-based Rethink Robotics. While Baxter’s body remains a fairly typical production line arm, his interface has been fitted with two motion-sensitive cartoon eyes, which provide just enough identity to press the Darwinian buttons necessary to encourage interaction, without being human enough to trigger the uncanny valley effect.

Such designs will likely be the future of public-facing robotics.

2. Social interaction will replace function

Currently, most consumer-facing robots are designed to be purely functional. From aerial delivery drones through to automated vacuum cleaners, most robots are programmed to serve, not to communicate.

But over the next five years this relationship will begin to evolve, with personal assistant applications such as Apple’s Siri already getting consumers used to the idea of speaking to devices in a naturalistic way.

With similar complex speech-recognition software being adopted across the robotics industry, a rapid shift away from functional machines towards social companions is probable.

Already in 2015 several social robots have been launched. Last month, RoboKind launched Milo, a robotic companion designed to help children with autism develop their social skills.

This year also saw more than $2.2m raised via the crowdfunding site Indiegogo for the development of Jibo, an autonomous ‘helper’ for the family home.

While these developments may seem like works of science fiction, the rise of the IoT has allowed consumer robotics to rapidly become a reality.

With almost 25 billion connected devices in the world, robots like Jibo are now able to function in a social context as a result of their interactions with the connected devices that surround them.

The more items (and ultimately robots) that are added to this network, the more ‘intelligent’ these machines can become.

3. Intelligence will be regulated

Professor Stephen Hawking drew media attention recently after he controversially stated that the development of artificial intelligence (AI) could spell “the end of the human race”.

While many technologists would consider this as nothing more than Luddite fear-mongering, the truth is that Hawking is not alone in his concerns. In fact, both Bill Gates and Elon Musk – hardly technological Luddites – have agreed with the statement, claiming that AI may be “the biggest existential threat” faced by humanity.

As a result there is a growing movement among tech professionals who want to see the development of AI robotics increasingly regulated. In 2009, the Association for the Advancement of Artificial Intelligence (AAAI) held its first conference to discuss whether robots could ever achieve a dangerous degree of autonomy.

More recently, Demis Hassabis – founder of Google’s secretive ‘Deep Mind’ AI project – came together with numerous researchers and industry professionals to develop a ‘Magna Carta for AI’. According to one Google spokesperson, this document was designed to flesh out the ethics governing AI, ultimately making sure that Hawking’s fears are never realised.

While we can’t know for sure how this regulation will be achieved – whether through government intervention or industry-supported standards – what is clear is that artificial intelligence will prove to be a significant point of contention over the next five years.

4. Drones will become de-politicised

One area of robotics that has received widespread interest over the past few years has been the adoption of drones in the consumer and industrial space.

Originally developed for use in military applications, drones have proved a highly controversial topic in the mainstream media. Yet despite the controversy, the past six months have seen a surge in consumer adoption, with radio-controlled drones being offered as everything from bird-watching appliances through to high-end children’s toys.

At the same time, many businesses have begun to consider how drones can be used to improve efficiency in their supply chains and even for home delivery systems.

While many of these applications have represented little more than publicity stunts, the truth is that unmanned drones are already being used in a number of real – and often extremely positive – settings. From providing antibiotics to hospitals in the Himalayas, to delivering university textbooks to students in Sydney, unmanned drones are far more than just a PR gimmick.

As these real life use-cases become increasingly common, drones are likely to become quickly depoliticised in the consumer landscape. While their tricky regulation and original military application may present some difficulties, the potential benefits of unmanned delivery and an increasing number of applications will quickly outweigh such concerns.

5. Cheap hardware will boost ‘makers’

Above all else, the key driving force behind the wider adoption of consumer robotics will be the falling cost of individual hardware components.

This reduction is being driven in part by the popularity of smartphones, with many common robotics components (cameras, sensors, voice recognition) now being mass-produced for use in mobile phones. As a result, the idea of having a personal robot is no longer just the dream of multi-millionaires, but something that will soon become a reality for ordinary people all over the world.

Additionally, according research by Dmitry Grishin, head of Grishin Robotics – the world’s largest venture capital fund devoted solely to developing robots – the future of robotics is also being driven by the growing popularity of low-cost electronics such as the Raspberry Pi and open source Arduino boards. Such low-cost components have led to a revitalisation of the home-robotics movement, with hobbyists being able to build their own autonomous devices for a fraction of past prices.

As reductions in cost help to open up robotics development to a far wider user base and audience a significant boost in the number of robot-focused start-ups is likely over the next five years.

At the same time, however, low-cost circuitry will not necessarily be enough to drive this movement. Adequate power supply is still going to prove a significant issue for consumer robotics, with many robots still struggling with an uneven weight-to-power ratio.

Sadly, while Moore’s law may have helped to significantly reduce the size and cost of internal circuits, batteries and motors still have a long way to go before they can meet the demands that will make consumer robotics a reality.

Simon Holt is marketing manager at element14

Richard Wilson

Five things you should know about AI and robots

From de-politicised drones to intelligent vacuum-cleaners and AI, this could be the future of robotics described in five technology predictions, writes Simon Holt.

Industrial-standard robotic components, assembled with the most basic simulcrum of a face invites interaction

Industrial-standard robotic components, assembled with the most basic simulcrum of a face invites interaction

Robots have a bit of a mixed reputation in the media. One minute they’re vacuum cleaning our homes and delivering our pizzas, the next they’re stealing our jobs and threatening to take over the world.

Thanks to more than 100 years of science fiction books and TV shows, robots remain controversial: they’re either destined to save the planet, or doomed to destroy it.

But how much of this rhetoric is true? With more than 8.6 million robots in existence, and the field of robotics recently being pegged as the “fastest growing industry in the world”, we find ourselves increasingly wondering what this robot-overrun future will look like.

Are robots to be feared, or embraced? More importantly, what is a robot? Should we be counting automated vacuum cleaners and self-service checkouts as part of the new robotics revolution, or are these simply more examples of the ever-expanding internet of things (IoT)?

In an attempt to answer some of these questions, I undertook a review of the most revolutionary robotics developments expected to appear in hospitals, shop floors and workplaces.

The five key predictions for the next five years are outlined below, along with the core challenges they present to the industry, and the areas to watch for the future direction of robotics.

1. Design will bridge the uncanny valley

The so-called ‘uncanny valley’ refers to an aesthetic hypothesis which states that when features look and move almost – but not exactly – like natural beings, the typical response is one of discomfort, or even revulsion.

In response to this hypothesis the production of robotics has focused far more on the development of autonomous machines than on ‘humanoid’ robots.

While it seems unlikely that human beings will ever conquer this response, humanoid aesthetics are nevertheless increasingly vital to the success of many upcoming robotics projects.

As robots increasingly replace workers in a variety of service and social contexts (hospitals and care homes, for example) the need for anthropomorphic features will become increasingly important.

Social technologist Sherry Turkle claims that “a robotic face is an enabler; it encourages us to imagine that robots can put themselves in our place and that we can put ourselves in theirs”.

Based on this growing demand for “lifelike” robots, it is increasingly important that developers overcome the uncanny valley effect.

To achieve this robotic engineers will increasingly turn to semi-humanoid developments, which maintain a traditional machine form, while also boasting very basic – even cartoonish – human features.

A recent example is Baxter, a newly launched robot from Boston-based Rethink Robotics. While Baxter’s body remains a fairly typical production line arm, his interface has been fitted with two motion-sensitive cartoon eyes, which provide just enough identity to press the Darwinian buttons necessary to encourage interaction, without being human enough to trigger the uncanny valley effect.

Such designs will likely be the future of public-facing robotics.

2. Social interaction will replace function

Currently, most consumer-facing robots are designed to be purely functional. From aerial delivery drones through to automated vacuum cleaners, most robots are programmed to serve, not to communicate.

But over the next five years this relationship will begin to evolve, with personal assistant applications such as Apple’s Siri already getting consumers used to the idea of speaking to devices in a naturalistic way.

With similar complex speech-recognition software being adopted across the robotics industry, a rapid shift away from functional machines towards social companions is probable.

Already in 2015 several social robots have been launched. Last month, RoboKind launched Milo, a robotic companion designed to help children with autism develop their social skills.

This year also saw more than $2.2m raised via the crowdfunding site Indiegogo for the development of Jibo, an autonomous ‘helper’ for the family home.

While these developments may seem like works of science fiction, the rise of the IoT has allowed consumer robotics to rapidly become a reality.

With almost 25 billion connected devices in the world, robots like Jibo are now able to function in a social context as a result of their interactions with the connected devices that surround them.

The more items (and ultimately robots) that are added to this network, the more ‘intelligent’ these machines can become.

3. Intelligence will be regulated

Professor Stephen Hawking drew media attention recently after he controversially stated that the development of artificial intelligence (AI) could spell “the end of the human race”.

While many technologists would consider this as nothing more than Luddite fear-mongering, the truth is that Hawking is not alone in his concerns. In fact, both Bill Gates and Elon Musk – hardly technological Luddites – have agreed with the statement, claiming that AI may be “the biggest existential threat” faced by humanity.

As a result there is a growing movement among tech professionals who want to see the development of AI robotics increasingly regulated. In 2009, the Association for the Advancement of Artificial Intelligence (AAAI) held its first conference to discuss whether robots could ever achieve a dangerous degree of autonomy.

More recently, Demis Hassabis – founder of Google’s secretive ‘Deep Mind’ AI project – came together with numerous researchers and industry professionals to develop a ‘Magna Carta for AI’. According to one Google spokesperson, this document was designed to flesh out the ethics governing AI, ultimately making sure that Hawking’s fears are never realised.

While we can’t know for sure how this regulation will be achieved – whether through government intervention or industry-supported standards – what is clear is that artificial intelligence will prove to be a significant point of contention over the next five years.

4. Drones will become de-politicised

One area of robotics that has received widespread interest over the past few years has been the adoption of drones in the consumer and industrial space.

Originally developed for use in military applications, drones have proved a highly controversial topic in the mainstream media. Yet despite the controversy, the past six months have seen a surge in consumer adoption, with radio-controlled drones being offered as everything from bird-watching appliances through to high-end children’s toys.

At the same time, many businesses have begun to consider how drones can be used to improve efficiency in their supply chains and even for home delivery systems.

While many of these applications have represented little more than publicity stunts, the truth is that unmanned drones are already being used in a number of real – and often extremely positive – settings. From providing antibiotics to hospitals in the Himalayas, to delivering university textbooks to students in Sydney, unmanned drones are far more than just a PR gimmick.

As these real life use-cases become increasingly common, drones are likely to become quickly depoliticised in the consumer landscape. While their tricky regulation and original military application may present some difficulties, the potential benefits of unmanned delivery and an increasing number of applications will quickly outweigh such concerns.

5. Cheap hardware will boost ‘makers’

Above all else, the key driving force behind the wider adoption of consumer robotics will be the falling cost of individual hardware components.

This reduction is being driven in part by the popularity of smartphones, with many common robotics components (cameras, sensors, voice recognition) now being mass-produced for use in mobile phones. As a result, the idea of having a personal robot is no longer just the dream of multi-millionaires, but something that will soon become a reality for ordinary people all over the world.

Additionally, according research by Dmitry Grishin, head of Grishin Robotics – the world’s largest venture capital fund devoted solely to developing robots – the future of robotics is also being driven by the growing popularity of low-cost electronics such as the Raspberry Pi and open source Arduino boards. Such low-cost components have led to a revitalisation of the home-robotics movement, with hobbyists being able to build their own autonomous devices for a fraction of past prices.

As reductions in cost help to open up robotics development to a far wider user base and audience a significant boost in the number of robot-focused start-ups is likely over the next five years.

At the same time, however, low-cost circuitry will not necessarily be enough to drive this movement. Adequate power supply is still going to prove a significant issue for consumer robotics, with many robots still struggling with an uneven weight-to-power ratio.

Sadly, while Moore’s law may have helped to significantly reduce the size and cost of internal circuits, batteries and motors still have a long way to go before they can meet the demands that will make consumer robotics a reality.

Simon Holt is marketing manager at element14

Richard Wilson

Novel downconverter design for fast scopes

There are technical challenges involved with the architecture of the frequency interleaving that has been used to date in gigahertz bandwidth oscilloscopes, writes Dean Miles.

Figure 1: The DSP task for real-time oscilloscopes is ‘stritching’ together the upper and lower spectral halves of the scope passband

Figure 1: The DSP task for real-time oscilloscopes is ‘stritching’ together the upper and lower spectral halves of the scope passband

Rising data communication rates are driving the need for very high bandwidth real-time oscilloscopes in the range of 60GHz-70GHz. These instruments are essential for validating and debugging new designs in coherent optical modulation analysis, high energy physics research, high speed data communications and other ultra‑wideband applications.

Historically, frequency interleaving technologies have been implemented to achieve extended frequency bandwidth coverage.

In the case of an oscilloscope channel, setting the local oscillator frequency to equal the mid-band of the analogue front‑end bandwidth allows the possibility to acquire the upper half of the scope passband with one analog‑to‑digital converter (ADC), and the lower half of the passband with a another ADC.

Reconstructing the total waveform by ‘stitching’ together the upper and lower spectral halves becomes a digital signal processing (DSP) task for today’s digital real-time oscilloscopes, as illustrated in Figure 1.

However, there are challenges inherent in this design approach. Once the acquisition has completed, and the data is in waveform memory, it is necessary to up-convert the upper band back to its original frequency range using digital signal processing techniques (DSP).

Recovering the two spectral ‘halves’ and reconstructing the waveform is complicated. Because the paths are not identical, it is necessary to compensate for the differences in the calibration that is part of the DSP.

Furthermore, due to the sharp bandpass filters used on the two spectral halves, recovering the exact centre of the spectrum is problematic, with potential amplitude flatness and phase linearity shifts.

Figure 2: Latency frequency interleaving

Figure 2: Latency frequency interleaving

As shown in Figure 2, each ADC only sees half the frequency spectrum and due to the reconstruction process involving a summation of both separate paths, there is no improvement possible in the signal-to-noise ratio.

Technical challenges

There are technical challenges involved with the architecture of the frequency interleaving that has been used to date in gigahertz bandwidth oscilloscopes.

To address these challenges a new approach can avoid some of the disadvantages of digital bandwidth interleaving (DBI), while still accomplishing the end result of extended bandwidth with existing ADCs.

With asynchronous time interleaving (ATI), a pre-sampler is used as a harmonic mixer. Figure 3 illustrates the block diagram of the asynchronous time interleave circuit.

Tektronix_ATI-Figures 3

Figure 3: An asynchronous time interleave circuit (ATI), where a pre-sampler is used as a harmonic mixer

One of the things that jumps out at first glance in this design is that the paths are symmetrical. There are no significant differences in propagation delay or phase shift between the two sides of the acquisition channel.

This simplifies the post-acquisition process of DSP re-mixing or reconstruction, as compared with DBI/frequency interleaving, minimising the amount of error at the mid‑band crossover. With ATI, the entire bandwidth of the signal is applied to both ADCs. In this way, the power spectral density of the noise is evenly spread across the total sample rate, which is twice the sample rate of the individual ADCs.

The result is that the overall noise in the passband is lower than it would be in the comparable DBI architecture.

Using a pre-sampler

Because harmonic mixing and time sampling are really the same thing, it is possible to accomplish the mixing shown in the ATI circuit diagram (Figure 3) using a pre-sampler.

This design uses the pre-sampler to intentionally sub-sample the input signal, thereby aliasing or folding the upper half of the spectral content back into the Nyquist bandwidth of the ADC.

For example, a 70GHz system could be achieved by running the asynchronous sample clock at 75GHz. This would result in the upper half of the 70GHz signal being aliased back into the range of DC to 37.5GHz.

The resulting data from the pre‑sampler could then be sampled by the ADC at a rate independent from the pre-sampler, such as 100GS/s. Note that the pre-sampler is running asynchronously from the ADC sample clock.

Figure 4: Complete block diagram for the asynchronous time interleave channel, indicating the spectral content of the signal at key points in the acquisition channel

Figure 4: Complete block diagram for the asynchronous time interleave channel, indicating the spectral content of the signal at key points in the acquisition channel

Figure 4 illustrates a more complete representation of the block diagram for the asynchronous time interleave channel, with an indication of the spectral content of the signal at key points in the acquisition channel.

As can be seen, the entire spectrum is applied to the preamp, and passes through the splitter to each pre‑sampler.

The output of the pre-sampler is a spectrum that contains a difference spectrum of the upper band folded back onto the lower band range, as well as the sum spectrum of the lower band overlaid on the upper band range.

This complex spectrum is then passed through a low pass filter that removes the upper band range, but passes the lower band (including the folded back upper band content) intact. This filtered signal is then passed to the track and hold, and captured by the ADC.

Once the acquisition is complete, and the data is stored into memory, the original signal can be recovered by re-mixing the signal digitally using DSP techniques.

At this point, rather than a physical asynchronous sampling clock signal, a mathematical representation of that asynchronous sampling clock signal can be used as input to the digital mixer, taking care that the phase relationship between the original analog asynchronous sampling clock and the mathematical representation of that signal are identical.

Note that the two pre-samplers are 180° out of phase. This is important when it comes to reconstruction of the signal.
After the digital mixing step of signal reconstruction, the numerical signal contains the sum and difference spectral content from the original acquired data.

Conveniently, during the final combining of the signals, the portions of the spectrum that are 180° out of phase cancel, and all that is left is the original spectrum, plus a portion of the sum spectrum which is removed with a 75GHz low pass filter.

This leaves only the content from DC to 70GHz that was originally applied to the scope for acquisition.
The final combining step is essentially a summation divided by two. This function returns the input amplitudes to their original value, but also has the effect of averaging the noise of the overall acquisition, thereby further reducing the total noise of the measurement channel.

Tektronix’ DPO77002SX 70GHz oscilloscope is the first production model incorporating ATI technology.

Dean Miles is technical marketing manager at Tektronix

Richard Wilson

Novel downconverter design for fast scopes

There are technical challenges involved with the architecture of the frequency interleaving that has been used to date in gigahertz bandwidth oscilloscopes, writes Dean Miles.

Figure 1: The DSP task for real-time oscilloscopes is ‘stritching’ together the upper and lower spectral halves of the scope passband

Figure 1: The DSP task for real-time oscilloscopes is ‘stritching’ together the upper and lower spectral halves of the scope passband

Rising data communication rates are driving the need for very high bandwidth real-time oscilloscopes in the range of 60GHz-70GHz. These instruments are essential for validating and debugging new designs in coherent optical modulation analysis, high energy physics research, high speed data communications and other ultra‑wideband applications.

Historically, frequency interleaving technologies have been implemented to achieve extended frequency bandwidth coverage.

In the case of an oscilloscope channel, setting the local oscillator frequency to equal the mid-band of the analogue front‑end bandwidth allows the possibility to acquire the upper half of the scope passband with one analog‑to‑digital converter (ADC), and the lower half of the passband with a another ADC.

Reconstructing the total waveform by ‘stitching’ together the upper and lower spectral halves becomes a digital signal processing (DSP) task for today’s digital real-time oscilloscopes, as illustrated in Figure 1.

However, there are challenges inherent in this design approach. Once the acquisition has completed, and the data is in waveform memory, it is necessary to up-convert the upper band back to its original frequency range using digital signal processing techniques (DSP).

Recovering the two spectral ‘halves’ and reconstructing the waveform is complicated. Because the paths are not identical, it is necessary to compensate for the differences in the calibration that is part of the DSP.

Furthermore, due to the sharp bandpass filters used on the two spectral halves, recovering the exact centre of the spectrum is problematic, with potential amplitude flatness and phase linearity shifts.

Figure 2: Latency frequency interleaving

Figure 2: Latency frequency interleaving

As shown in Figure 2, each ADC only sees half the frequency spectrum and due to the reconstruction process involving a summation of both separate paths, there is no improvement possible in the signal-to-noise ratio.

Technical challenges

There are technical challenges involved with the architecture of the frequency interleaving that has been used to date in gigahertz bandwidth oscilloscopes.

To address these challenges a new approach can avoid some of the disadvantages of digital bandwidth interleaving (DBI), while still accomplishing the end result of extended bandwidth with existing ADCs.

With asynchronous time interleaving (ATI), a pre-sampler is used as a harmonic mixer. Figure 3 illustrates the block diagram of the asynchronous time interleave circuit.

Tektronix_ATI-Figures 3

Figure 3: An asynchronous time interleave circuit (ATI), where a pre-sampler is used as a harmonic mixer

One of the things that jumps out at first glance in this design is that the paths are symmetrical. There are no significant differences in propagation delay or phase shift between the two sides of the acquisition channel.

This simplifies the post-acquisition process of DSP re-mixing or reconstruction, as compared with DBI/frequency interleaving, minimising the amount of error at the mid‑band crossover. With ATI, the entire bandwidth of the signal is applied to both ADCs. In this way, the power spectral density of the noise is evenly spread across the total sample rate, which is twice the sample rate of the individual ADCs.

The result is that the overall noise in the passband is lower than it would be in the comparable DBI architecture.

Using a pre-sampler

Because harmonic mixing and time sampling are really the same thing, it is possible to accomplish the mixing shown in the ATI circuit diagram (Figure 3) using a pre-sampler.

This design uses the pre-sampler to intentionally sub-sample the input signal, thereby aliasing or folding the upper half of the spectral content back into the Nyquist bandwidth of the ADC.

For example, a 70GHz system could be achieved by running the asynchronous sample clock at 75GHz. This would result in the upper half of the 70GHz signal being aliased back into the range of DC to 37.5GHz.

The resulting data from the pre‑sampler could then be sampled by the ADC at a rate independent from the pre-sampler, such as 100GS/s. Note that the pre-sampler is running asynchronously from the ADC sample clock.

Figure 4: Complete block diagram for the asynchronous time interleave channel, indicating the spectral content of the signal at key points in the acquisition channel

Figure 4: Complete block diagram for the asynchronous time interleave channel, indicating the spectral content of the signal at key points in the acquisition channel

Figure 4 illustrates a more complete representation of the block diagram for the asynchronous time interleave channel, with an indication of the spectral content of the signal at key points in the acquisition channel.

As can be seen, the entire spectrum is applied to the preamp, and passes through the splitter to each pre‑sampler.

The output of the pre-sampler is a spectrum that contains a difference spectrum of the upper band folded back onto the lower band range, as well as the sum spectrum of the lower band overlaid on the upper band range.

This complex spectrum is then passed through a low pass filter that removes the upper band range, but passes the lower band (including the folded back upper band content) intact. This filtered signal is then passed to the track and hold, and captured by the ADC.

Once the acquisition is complete, and the data is stored into memory, the original signal can be recovered by re-mixing the signal digitally using DSP techniques.

At this point, rather than a physical asynchronous sampling clock signal, a mathematical representation of that asynchronous sampling clock signal can be used as input to the digital mixer, taking care that the phase relationship between the original analog asynchronous sampling clock and the mathematical representation of that signal are identical.

Note that the two pre-samplers are 180° out of phase. This is important when it comes to reconstruction of the signal.
After the digital mixing step of signal reconstruction, the numerical signal contains the sum and difference spectral content from the original acquired data.

Conveniently, during the final combining of the signals, the portions of the spectrum that are 180° out of phase cancel, and all that is left is the original spectrum, plus a portion of the sum spectrum which is removed with a 75GHz low pass filter.

This leaves only the content from DC to 70GHz that was originally applied to the scope for acquisition.
The final combining step is essentially a summation divided by two. This function returns the input amplitudes to their original value, but also has the effect of averaging the noise of the overall acquisition, thereby further reducing the total noise of the measurement channel.

Tektronix’ DPO77002SX 70GHz oscilloscope is the first production model incorporating ATI technology.

Dean Miles is technical marketing manager at Tektronix

Richard Wilson

Regulator delivers low 100mV dropout voltage for cars

micrelA low-dropout voltage regulator (LDO) for automotive AEC-Q100 qualified designs from Micrel has a dropout of only 100mV at 300mA.

The MAQ5300 has a 300mA output current and is available in numerous fixed output voltage options of 1.5V, 1.8V, 2.5V, 2.8V, 2.85V, 3.0V, and 3.3V.

Other features include an initial precise output voltage accuracy of ±2%, low shutdown quiescent current of 0.1µA, thermal shutdown and current limit protection.

The MAQ53200 device is available in a 6-pin 2 x 2mm DFN package.

There is expected to be an increase in the designing in of camera modules and image sensors in the next two years as the National Highway Traffic Safety Administration in the US introduces legislation which will require all new passenger, and some commercial vehicles, to meet new rear-visibility standards by May 2018.

 

 

  

Richard Wilson

Regulator delivers low 100mV dropout voltage for cars

micrelA low-dropout voltage regulator (LDO) for automotive AEC-Q100 qualified designs from Micrel has a dropout of only 100mV at 300mA.

The MAQ5300 has a 300mA output current and is available in numerous fixed output voltage options of 1.5V, 1.8V, 2.5V, 2.8V, 2.85V, 3.0V, and 3.3V.

Other features include an initial precise output voltage accuracy of ±2%, low shutdown quiescent current of 0.1µA, thermal shutdown and current limit protection.

The MAQ53200 device is available in a 6-pin 2 x 2mm DFN package.

There is expected to be an increase in the designing in of camera modules and image sensors in the next two years as the National Highway Traffic Safety Administration in the US introduces legislation which will require all new passenger, and some commercial vehicles, to meet new rear-visibility standards by May 2018.

 

 

  

Richard Wilson

5G radio baseband analysis may not need mixers

22jul15RSTesting mobile baseband and RF with a single analyser without external harmonic mixers is a feature of the latest signal and spectrum analyser from Rohde & Schwarz.

The FSW85 covers the frequency range from 2Hz to 85GHz in a single sweep.

An internal preselection suppresses the image frequency and other spurious emissions that commonly occur during harmonic mixing.

The analyser options include an internal analysis bandwidth of 500MHz, which will be relevant for developers of radar components in automotive and aerospace applications.

When combined with the FSW-B2000 option and an RTO oscilloscope, it is possible to achieve an analysis bandwidth of 2GHz.

This will allow developers to analyse broadband signals for 5G next-generation mobile communications signals or complex pulse parameters and chirp signals for radar systems.

Rohde & Schwarz will be presenting the analyser at European Microwave Week 2015 in Paris in September.

 

Richard Wilson

5G radio baseband analysis may not need mixers

22jul15RSTesting mobile baseband and RF with a single analyser without external harmonic mixers is a feature of the latest signal and spectrum analyser from Rohde & Schwarz.

The FSW85 covers the frequency range from 2Hz to 85GHz in a single sweep.

An internal preselection suppresses the image frequency and other spurious emissions that commonly occur during harmonic mixing.

The analyser options include an internal analysis bandwidth of 500MHz, which will be relevant for developers of radar components in automotive and aerospace applications.

When combined with the FSW-B2000 option and an RTO oscilloscope, it is possible to achieve an analysis bandwidth of 2GHz.

This will allow developers to analyse broadband signals for 5G next-generation mobile communications signals or complex pulse parameters and chirp signals for radar systems.

Rohde & Schwarz will be presenting the analyser at European Microwave Week 2015 in Paris in September.

 

Richard Wilson

Gold medal-winner David Stone to speak at ECSN dinner

Stone

David Stone

Electronic Components Supply Network (ECSN) which represents the UK component supply chain will hold its industry dinner on 8th October in the Holiday Inn Hotel, Brighton.

In keeping with recent ECSN dinners, there will be an open discussion session with national and international industry executives.

The after-dinner keynote presentation this year will be delivered by David Stone MBE, the gold medal-winning para-cycling Olympian.

The is the 45th anniversary of the industry dinner, which this year is being sponsored by Mouser Electronics.

“People from all sections of our industry have come to recognise what a great opportunity the event is for meeting up with friends and industry contacts past and present over a drink and an excellent meal,” commented ECSN chairman, Adam Fletcher.

You can book your place at the dinner on the ECSN website.

Richard Wilson