Why 77GHz Radar Is Replacing 24GHz as the New Standard
- Mrunal Upadhye
- Aug 21, 2025
- 7 min read
Vehicles are no longer basic transportation. They’re becoming intelligent machines. This shift is changing how vehicles sense their surroundings and make driving decisions. Radar technology has driven much of this transformation. Early systems ran on 24GHz radar.
That frequency supported the first generation of ADAS (Advanced Driver Assistance Systems). But demands on these systems have grown. Now, the industry is moving to 77GHz radar as the new standard.
Why is this transition happening, and what makes 77GHz superior? Let’s break it down.
The Role of Radar in Modern Vehicles
Radar systems form the backbone of ADAS. They support key features such as adaptive cruise control, collision warning, blind spot detection, and autonomous emergency braking. These systems measure the range, speed, and position of nearby objects. They remain effective even in low visibility conditions.
For years, 24GHz radar was common in short-range applications. It was cost-effective, simple to design, and delivered what early ADAS systems needed. But as vehicle automation has advanced, the demands on radar have grown. Precision, range, and adaptability now matter more than ever.
Frequency Bands: 24GHz vs 77GHz
The 24 GHz band has two parts. The first is a narrowband (NB) range from 24.0 to 24.25 GHz. This range offers only 250 MHz of bandwidth. Regulators allow it for unlicensed use. Automakers use it in simple radar tasks such as basic blind spot detection. The second part is the ultra-wideband (UWB) range. It spans 5 GHz and gives better resolution for short-range radar.
For years, both NB and UWB supported early automotive radar sensors. Regulators in Europe and the U.S. have since phased out the UWB part. After January 1, 2022, carmakers could use only the narrowband section. That limited bandwidth weakens 24 GHz. It cannot support advanced ADAS features that demand high precision and long range.
The 77 GHz band solves these issues. The 76–77 GHz range works for long-range radar (LRR). It powers features such as adaptive cruise control. The 77–81 GHz range supports short-range radar (SRR) with up to 4 GHz of bandwidth. That wider range gives radars sharper resolution. It helps them separate objects with clarity and detect hazards sooner.
Global regulators in the U.S., Europe, and Japan support the 77 GHz band. The same band also serves industrial uses such as fluid and solid level sensing. As a result, most new radar systems are shifting from 24 GHz to 77 GHz. This shift positions 77 GHz as the long-term standard.
Limitations of 24GHz Radar
24GHz radar has been dependable for basic driver assistance. It has served in this role for many years. But modern vehicles now need higher precision, faster processing, and longer detection ranges. It can no longer meet the needs of advanced safety and automation systems.
Here’s why it’s losing relevance:
1. Limited Resolution
The 24GHz band has a narrow bandwidth between 100 and 250 MHz. This reduces range resolution. As a result, it becomes harder to separate objects that are close to each other.
In urban streets, intersections, and crowded parking areas, lower resolution creates challenges. Targets can blend. It also makes object identification less clear.
2. Short Detection Range
The effective detection range is only 30 to 50 meters. That works for low-speed maneuvering. But it doesn’t allow early hazard detection. Features like high-speed emergency braking, highway-level collision warning, and long-range adaptive cruise control need more reach. The 24GHz radar falls short.
3. Reduced Angular Precision
24GHz systems have a narrow field of view. They also offer lower angular resolution than higher-frequency radars like 77GHz. This makes it harder to pinpoint the exact lateral position of objects. The problem grows when tracking across multiple lanes.
It also limits multi-target tracking in dense traffic. In these situations, the system must separate one vehicle from another with precision.
4. Vulnerability to Interference
Reflective surfaces, heavy rain, and dense traffic can weaken 24GHz radar signals. These conditions increase the risk of false positives, ghost targets, or missed detections. In real-world driving, these issues reduce system reliability.
5. Regulatory Limitations
Some regions are phasing out 24GHz radar for automotive use. This shift comes from spectrum reallocation. Global standards now support the 77–81GHz band instead. It provides more bandwidth and stronger performance. As a result, 24GHz radar no longer fits long-term use in new vehicles.
Why 77GHz Radar is Gaining Momentum
77GHz radar addresses the limits of 24GHz and adds real advantages. ADAS keeps advancing, and radar must offer higher accuracy. It also needs a longer range and more flexibility.
77 GHz radar gives vehicles more bandwidth to work with than older 24 GHz systems. This extra range means sharper detection, better tracking of moving objects, and even the ability to spot cars or pedestrians that are close together.
That’s why 77GHz radar has become the preferred standard. It delivers strong performance and fits long-term global regulations.
1. Higher Resolution Through Greater Bandwidth
77GHz radar supports bandwidths up to 4GHz, giving it much finer range resolution. It can separate objects that are close together with precision.
For example, 77GHz radar can tell a pedestrian from a nearby lamppost. It can also spot the difference between a parked car and a slow-moving one. This kind of detail matters in cities, where traffic and hazards stay close.
2. Longer Detection Range
Operating at a higher frequency allows 77GHz radar to detect objects up to 250 meters ahead. This extra reach gives ADAS more time to process information and respond. The benefit is especially clear at highway speeds.
It works well for features like adaptive cruise control. This function helps maintain a safe distance from the vehicle ahead. It also supports forward collision warning, which depends on early detection.
3. More Compact and Flexible Design
At 77GHz, antennas and sensor modules can be smaller. They still deliver a strong performance. Automakers can place them behind bumpers or inside grilles without design trade-offs.
The compact size also supports multi-radar setups. These systems provide 360-degree monitoring. That coverage enables advanced safety features like lane change assist and automated parking.
4. Better Object Tracking and Accuracy
Higher angular resolution improves object tracking. 77GHz radar can track several moving objects at the same time. It stays accurate even in heavy traffic.
This accuracy supports smooth lane changes. It also enables blind spot detection and cross-traffic alerts. Fewer false alerts mean drivers get warnings that stay timely and useful.
5. Aligned with Global Regulations
Regulators around the world have approved the 77–81GHz band for automotive use. This makes it easier to use the same radar across different markets. At the same time, many regions are phasing out 24GHz due to spectrum reallocation.
For automakers, using 77GHz lowers the risk of future redesigns. It also keeps vehicles aligned with changing regulations.
6. Ready for Future Applications
77GHz makes 4D imaging radar possible. This adds height data to the usual range, speed, and angle measurements. That extra dimension improves scene understanding. For example, it can tell an overpass from a vehicle or spot small but important obstacles.
These capabilities matter as automated driving evolves. Higher levels of autonomy will depend on them.
Regulatory Requirements
Performance isn’t the only driver of 77GHz adoption. Regulations and policy changes are also shaping the Indian market.
Stricter Safety Standards:
India has been tightening road safety norms. With Bharat NCAP now in place, OEMs face rising pressure to add stronger ADAS features. Higher safety ratings will depend on systems such as emergency braking, pedestrian detection, and blind spot monitoring.
Each of these needs fast and accurate object recognition. That is where 77GHz radar makes the difference. It supports crash avoidance and keeps vehicles aligned with global safety benchmarks.
Spectrum Allocation and Policy in India:
The Telecom Regulatory Authority of India (TRAI) has recommended opening the 77–81GHz band for automotive radar. It would fall under a license-exempt framework. The plan follows global practice. It also adopts ITU-R M.2057-1 standards. These standards ensure radar systems meet global requirements for accuracy and safety.
The change would reduce regulatory uncertainty. It would also make compliance easier for OEMs and Tier-1 suppliers. High-resolution radar could then support both short- and long-range use. At the same time, the 24GHz band is losing ground. Regulators are shifting focus, which limits its role in future radar applications.
Global Harmonization with Local Benefits:
Regulators around the world are moving toward 77GHz as the common standard. India stands to gain from this shift. A single radar design can serve the Indian market and also meet rules in Europe, North America, and major Asian regions.
This lowers costs and makes production simpler. It also helps domestic OEMs expand into export markets. At the same time, it keeps India’s auto industry aligned with future policy changes in key regions.
Industry Adoption Trends
Regulation and performance gains have accelerated industry adoption. What started as a premium feature in high-end models is now becoming standard.
Bosch, Continental, and Aptiv now produce radar modules only in the 77–81GHz band. Their systems cover everything from short-range detection to highway automation.
Luxury brands like Mercedes-Benz, Audi, and BMW led the way. They used 77GHz radar for adaptive cruise control, lane keeping, and emergency braking. As production costs dropped, the technology moved into mid-range models.
Most forecasts point to 77GHz radar becoming standard in new passenger vehicles. This shift will likely happen within a few product cycles. It’s now a baseline for meeting global safety standards.
24GHz Radar: Where It Still Fits
24GHz is fading from safety-critical automotive roles. But it still fits use cases where cost or simplicity matters more than performance.
You’ll find it in:
24GHz still supports entry-level ADAS features. These include rear parking assistance and basic blind spot monitoring. Some markets still allow the band, which keeps it viable for now.
Consumer and industrial products like motion sensors, sliding doors, and automation systems
Some early in-cabin sensing prototypes used 24GHz radar. These included systems for gesture recognition and occupancy detection. Many of them have since moved to ultra-wideband or 60GHz solutions.
Integration with Sensor Fusion
What makes 77GHz radar valuable is how it works with other sensors. Radar provides steady speed and distance data, even in poor visibility. Cameras add visual detail. LiDAR brings depth and shape. Together, they give the system a stronger context and better decision-making ability.
This matters when vehicles face complex situations. The system must handle intersections. It also supports overtaking and maintains perception when something blocks a sensor.
As vehicle software advances, it relies more on structured, reliable inputs. 77GHz radar meets that need, supporting centralized processing and real-time decision-making.
Final Thoughts
The shift to 77GHz radar is redefining vehicle safety.
Starkenn’s automotive-grade 77GHz radar meets global standards and delivers the performance ADAS demands.
Get in touch to see how Starkenn Radar can drive the next generation of vehicles: contact@starkenn.com or visit www.starkenn.com
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